I think my most epic gaming moment came from Team Fortress Mega (Mod to the quake 1 mod). In 2fort5r (the same as 2 fort, only there was no overhead cover on the bridge and there are a pair of dogs out front of each base that keep you from camping there) the opposing ramp room was an utter death trap. In those days, I tended to favor the spy or the pyro, and after being completely ineffective as a pyro (not so good when trying to bust into an entrenched position oddly) I swapped over to spy.
Now, to paint the scene, the ramp room itself was being defended by a pair of sentry guns (which were actually significantly more lethal in those days), a Heavy Weapons Guy, a Demo man and a pair of engineers. One of the many differences about TF Mega was the inclusion of a special dropped item for each class - as a spy, you had an ammo trap that took all the opponents ammo except the round in the gun. Disguised as a demo man, I walked into the room and quickly examined my options. I let my team know that chaos was about to ensue, so obviously they should attack at once as it would probably be their best chance to break through the strongpoint.
My plan literally was simply "cause chaos" - I never intended to actually do any direct good in my action. So, I delivered my ammo trap to the heavy, unnoticed at first it seems as he didn't react to my action. I then threw my four gas grenades (DOT, plus hallucination and in Mega the thrower was immune to it's effects), and at that moment chaos ensued. Unsure as to who was the culprit, the defenders started shooting at one another, and I quickly pitched my frag greandes at the pair of sentries, dispatching both the guns and their baby sitting engineers. As the heavy was trying to escape and I was no longer in danger fron the deadly automated guns, I quickly tranqulized the heavy, then swapped to my shotgun and dispatched the demoman, clearly weakened from the gas. Just as they heavy was about to escape, I finished him off with a quick and brutal shanking session.
At this point I was quite confused as things were going far better than I had hoped. Because my plan didn't make it this far, the only thing I could think to do was try and grab the flag, so after snagging some ammunition from a backpack (including more grenades) I jumped down the elevator shaft (formerly the back ramp leading to the intelligence room in TF2 was a long shaft with a friendly only elevator, meaning only two classes could actually use it as an exit during an attack). I reapplied my demoman disguise and walked into the flag room to find it guarded by a sentry with no engineer seemingly present. The sentry was rapidly taken care of with another pair of grenades and the flag was mine, or so I thought. It turns out that the engineer had simply gone off to acquire more metal, and we met in the outer hallway, but luck was on my side it seems because again my shotgun proved his unodoing.
Back in those days, the spy had another little trick up his sleeve - a grappling hook. It was essentially a one shot deal as it used your entire supply of energy cells to fire, but usually that was all you needed. Using the hook I quickly exited the lower portion of the enemy base. Once again I had reached a decision point. The front door was the quickest way to get out of the base but surely such a move would be expected and it would likely be heavily guarded. The sniper deck was equally risky but I figured many of the potential defenders would have moved down the spiral stair hoping to find the cheeky bastard who made off with the flag, so I resolved to take the upper deck exit. Finding it seemingly undefended, I pitched another gas grenade to help cover my escape.
One last update on TF Mega - the game had items called "toasters" - a special grenade like item that, when pitched in water, tended to instantly kill any enemies occuping said water (it worked on line of sight so if you were in the tunnels it wouldn't necessarily kill you if it was pitched into the water near the bridge). The thing cost two secondary greandes to throw - and as luck would have it I had exactly two of those grenades and a full stock of energy cells.
It is at this point in the tale (i'm still on the sniper deck) that things got especially hairy. A good portion of the enemy team was respawning after their latest escapades and the began pouring out of the sniper deck respawn point. Knowing I couldn't make the run across the bridge with my woeful amount of health (and in those days if the flag landed in the open it was basically lost, as moving it more than an inch at at time required your entire team and a lot of luck), I opted for an even more risky maneuver (considering the toasters): I jumped straight into the water. The moment I hit, I immediately loocked up (in those days you couldn't see below the surface from above and vice versa) and just guessed as to where the bridge was. My grappling hook whirred away and a fraction of a second later I was greeted by a reassuring thunk as it hit home. I hoisted myself from the water just as a half dozen (or more) toasters poured into the water, rapidly followed by several members of the opposing team eager to finish the job. Using my last two special grenades, I pitched my own toaster into the water and this last attempt to stop me ws foiled.
The rest of my run to cap the flag was uneventful. Unfortunately I was doomed to never do anything of note again for the rest of the game, because clearly when you become a badass on par with james bond for even a few moments, the universe has to kick you in the shins.