Good idle animations are, to me, one of those things that can set apart a good game from a great one, since it feels like polish. It's completely useless, and something no developer actually has to do, but seeing them put in the extra effort of adding one, or even better, more than one idle animation just warms my heart. The first thing I do whenever I start a new game is just stand there for a minute. Usually I'll get something, but sometimes there's nothing, and I spend the first 30 minutes feeling kinda depressed.

A short list of idle animation descriptions in some big (and some smaller) games can be found here:
http://en.wikipedia.org/wiki/Idle_animations

But video footage is of course always better.

The one I always think first of whenever I think of idle animations, because it shocked the hell out of me, Raziel in Soul Reaver 2: http://www.youtube.com/watch?v=a12IGdRIbuU

Looking on youtube, either I am completely looking the wrong way, or there is a disturbing lack of idle animation videos/compilations.

One good one I did find is this, Legion from Mass Effect 2: http://www.youtube.com/watch?v=ZwzoedQ_ZQ8

As games get higher budgets and start looking better and better, I feel idle animations have developed as well, for better or worse. They look better, but feel less special, since these days everything uses a ton of animation. A good example is Uncharted. It looks amazing but at the same time it feels like Drake is doing an idle animation as soon as you leave him alone for a second. Of course, I can't deny that Uncharted is polished to hell and back, so I guess I'm kinda contradicting myself, but whatever.

Anyone else have any favorites? Or do you just not care/never leave the controls alone long enough to see them?

The classic Sonic 'Im waiting' tap foot or Earthworm Jim skipping with his body.

I love some of the Midna idle animations when she's riding wolf link in Twilight Princess.

Crash Bandicoot.

Crash Bandicoot? I don't remember what he does... juggle with wumpa fruits?

@RazielCuts said:

The classic Sonic 'Im waiting' tap foot or Earthworm Jim skipping with his body.

That's the first one that came to mind for me, I'm not sure I remember any others.

Mario has good one when he takes a nap.

I always liked Crash Bandicoot's idle animations. He did all sorts of stuff. He'd juggle with wumpa fruits, play with his yo-yo, do a weird dance thing. All sorts.

Crash Bandicoot. The yo-yo animation was always fun to see.

Sonic tapping his foot, staring directly into the camera is just about as iconic an idle animation as there is.