Everyone and their mother has linked to this, so you've probably already seen the photos that Jeff Bridges took when on-set for Iron Man. But, if you haven't, you can say you heard about it here first.
As I "thumbed" through Bridges' book I can't help but think that more people, like Jeff Bridges, should do this sort of thing. Keep a photo log of interesting things that they work on. All too often the only time we see celebrities is when they are on the red carpet or, worse, when they are doing something they'd rather not be public.
Source: Making Iron Man.