I like them and like to go after them as it sometimes gives me something other to do then just blast through a game. I have rules that I follow though.
1. I will not play a game JUST because the achievements are easy.
2. I will try to get all the single-player achievements possible (to the extent that I have a spreadsheet keeping track of it so that I know if I have completed all the achievements that are single player.)
A lot of people are mentioning Assassin's Creed, Mass Effect, and Call of Duty 4.
With regards to Assassin's Creed, the collection achievements are annoying but I personally like hunting this sort of thing because it gives me a reason to explore every inch of the world, which in this case had a lot of cool platforming between the cities.
Mass Effect has the right idea. The achievements for using the skills such as Singularity or Sniper Rifle would let you add that skill as a bonus to a new character on the next playthrough.
And finally Call of Duty 4. They are completely correct in making a fun multiplayer game with no multiplayer achievements. In my experience, many games are ruined online by multiplayer achievements as people are busy chasing them instead of just enjoying the game. Brothers in Arms: Hell's Highway also has a similar idea, with all 1000 points in single player mode while there are a few multiplayer achievements that are worth 0.
So in summary, yes I love my achievements because they add another element to the games that I love.