Your hidden gems!

[Tyrannical]

Well, depends on where you live. In Australia, here are some "hidden gems".
Tropico
Thief
Sid Meier's Pirates
Evil Genius

Love each and every one of em, especially evil genius.

 

[The Madman]

Little talked about games I think deserve more recognition? Oh jeez, that's a long list.

-Age of Wonders: Shadow Magic
-Call of Cthulhu: Dark Corners of the Earth
-Kings Bounty: The Legend
-Nexus: The Jupiter Incident
-Arx Fatalis
-Solium Infernum
-Avadon: The Black Fortress
-King Arthur: The Roleplaying War Game
-Rocket Knight Adventures

And a whole lot more.

Dark Messiah of Might and Magic and Arx Fatalis (both by the same developer, Arkane Studios), quickly became two of my favourite RPGs this year. I absolutely loved the first-person combat system in Dark Messiah, and Arx Fatalis was a wonderfully atmospheric first person dungeon crawl.

Hey, someone else who's played Arx Fatalis, we should form a gang.

 

[Baldr]

Tracer(Win 95) A cyberpunk puzzle game, I bought it at a garage sale for $5, almost all existence of it on the web has been lost to time.

It not a bad game, it would kill on the mobile market today. I wish I could get the rights for a port.

 

[dessertmonkeyjk]

I'd have to say Croc: Legend Of The Gobbos for the PC and it's imaginatively-named sequel, Croc 2. Sometimes, I think that me and my friends are the only damn people on the planet who know that game exists.

You're not.

What about... um... Sonic Advance 2? I was playing it a few hours ago and it feels quite spot on.

 

[Ultra Man30]

I have quite a few gems, as I am a collector of sorts, kinda. If I see an older game that didn't get much publicity and seems fun and interesting I try to find it and play it. That said, here are a few of my favorites:

Shadowman (N64/PC) - A fun adventure game that can take a bit longer than others. It's like Ocarina of Time, except with guns and a less linear world.
Gitaroo Man (PSP/PS2) - My personal favorite rhythm game. Has catchy music and is overall a fun game to play.
Odama (Gamecube) - An RTS mixed with a game of pinball. You order troops with the microphone while crushing enemies with a giant pinball.
Cubivore (Gamecube) - You play as a cube that must devour other cubes.
Psychonauts (Xbox/PC/Xbox-Live) - Probably the funniest game I have ever played. You have to delve into the minds of the many different characters. An action platformer of sorts.
Eternal Darkness (Gamecube) - A survival-horror type game with one of the most interesting spell-casting and fighting systems in almost any game I've played.
Billy Hatcher (Gamecube) - A 3-D platformer involving the rolling and hatching of eggs to complete the game.
LSD: the Dream Emulator (PS1) - A very interesting "game" that was only released in Japan that I am unable to describe. Just watch gameplay of it and you'll see why.
Chibi-Robo (Gamecube) - An adventure game where you play as a very small robot doing chores around a house. A whole lot more fun than it sounds.

I know a few more gems, but I think that these should provide some curiosity for now.

 

[Black Arrow Officer]

Rise of Nations. It's a fantastic RTS with great historical themes. Plus, the expansion pack lets you command a legion of WAR ELEPHANTS!!!

 

[EbonBehelit]

Jet Force Gemini on the N64 - one of the best games on the system (even in review scores), but it sold so poorly that Rare never bothered to make a sequel.

Also Shadowman on the same system - scared the everliving piss out of me back in the day.

From my GCN collection: Viewtiful Joe 1 & 2, Ikaruga, Skies of Arcadia: Legends, and Super Monkey Ball 2. Nobody I know has ever played any of them bar when I bring them to a get-together.

 

[Suicida1 Midget]

Looking through my games i found a few fun ones nobody really knows or talks about.
Golden Sun 1 and 2. These were my life back in the fifth and sixth grade. GBA

The Legend of Zelda Ocarina of Time Master Quest. This had the improved dungeons that make YOU THINK about the puzzels. Gamecube

Battalion Wars. It was quite fun, kinda like an rts, tps, and tower defense rolled into one. Gamecube.

Digimon World 4(i hope thats the right name) It was a unique adventure game. If you dont know where to go its kinda annoying. Hell i cant get past the venom jungle. But it made a good 4 person co-op game. GameCube/PS2

Stubbs the Zombie. Freaking fun. How many games lets you PLAY as the zombie starting the end of punchbowl? Xbox.

Destroy All Humames. Yeah funny game. You just need to play the first two. Cant vouch for any beyond that. Xbox/PS2

 

[neonsword13-ops]

It's good to see another person giving EDF some much deserved love.

Such a shame the fanbase is so small, it's a wonderful game.

It's one of those games that you can just pop in when a friend comes over and have hours of fun just annihilating waves of baddies.... and then the big ones come out... and it gets even funner. That's right, funner.

Indeed it is.

Just goes to show you, bags of chips, a couple of two liters, and a fun game can have you set for hours of fun.

And thousands of dead ants.

 

[Truehare]

It's been a long time since I last mentioned them, which is odd for me: Gothic I and II are fenomenal open-world RPGs which deserve a lot more recognition in a world obsessed with Morrowind and Oblivion (for the record: yes, I am also in love with Skyrim, it's the first Elder Scrolls game to really work for me). Gothic II is easily the best game I've ever played. And it's on GOG, which, as someone already suggested, you should check out if you haven't already.

Other than that, Zeus: Master of Olympus and its expansion are terrific city-building games. I wasted countless hours building the likes of Athens or Atlantis and protecting them from Hydra or Kraken. Maybe it's just that I love Greek mythology, but the games are fantastic.

Also,

Well, depends on where you live. In Australia, here are some "hidden gems".
(Other games I haven't played)
Evil Genius

Love each and every one of em, especially evil genius.

That's another great "city-builder"! Hard but fun game.

And:

Little talked about games I think deserve more recognition? Oh jeez, that's a long list.

-(A bunch of games I never played)
-Call of Cthulhu: Dark Corners of the Earth
-Arx Fatalis
-Rocket Knight Adventures

Those are absolute gems. I especially love Cthulhu (the game, not the entity), it's immersive as f%$#.

Hey, someone else who's played Arx Fatalis, we should form a gang.

Count me in! How many of us are there? Three?

 

[itsausernamewhatofit]

I'd have to say Croc: Legend Of The Gobbos for the PC and it's imaginatively-named sequel, Croc 2. Sometimes, I think that me and my friends are the only damn people on the planet who know that game exists.

I played both and have so many fond memories. I think I still have them somewhere downstairs.
Anyway I remember the Spy Fox series as being wonderful although i was playing them when I was 6 so I'm not sure it would pose much of a challenge for you. Such a great series. Now I want to replay those...
Try them out though.
EDIT:
Here's some footage of the amazing adventure you could be having

 

[Brutal Peanut]

One of the greatest games you've never played. Also, its prequels. Those were stupid fun, too. But alas, not many people have played it. Everyone I met online for co-op was just as surprised to find out there were actually others who loved the series.

Holy monkey balls, that looks awesome.

 

[DirgeNovak]

Are Primal and Ghosthunter obscure? If so, them. Incredible, incredible games.

 

[EbonBehelit]

Monster Hunter.

Seriously, people, check it out - it's basically a much better version of Demon's Souls.

Isn't Monster Hunter one of the most popular game series EVER in Japan?

 

[Jennacide]

Hmm, obvious choices are Grim Fandango and Planescape: Torment, but they at least have cult followings.

Soooo, in the really obscure category, how about Escape Velocity. (You'll want to mute this, he uses bad custom music)
The game came out for the Macintosh in like 1997, and if you watch the video you get a rough idea of how it plays, at least in combat. It's sorta like if Asteriods and Privateer had a baby. It plays like Asteroids in space sections, but has a ton of the depth of Privateer in starting from scratch. You attain your fortune through being a merchant, marine, bodyguard, or space pirate. Also the first game I remember modding for, putting in stuff like firing forklifts as a weapon.

Monster Hunter.

Seriously, people, check it out - it's basically a much better version of Demon's Souls.

1) That's not obscure, even remotely. It's the single most popular game series in Japan.
2) Demon's Soul/Dark Souls have far superior combat mechanics. Monster Hunter excels in far superior cooperative play.

 

[Setrus]

Heroes of Might and Magic: Dark Messiah

Seriously, that game is REALLY under-rated. It was amazing. I really really want to see another one like it.

good choice there, i loved that as well

It was an excellent game, especially with the multiple endings...though the plot moved a bit too quick for me, the combat more then made up for it. (sure, come closer to that spike-covered wall... )

 

[Rabish Bini]

Shit, I forgot about Evil Genius.

Go out and get Evil Genius immediately.

 

[Zyxzy]

I always thought Blast Corps, Vigilante 8, and War Of The Monsters were some fun games could use more love. Not masterpiece quality, but fun.