As a die-hard Nikon fan, I never thought I'd say this, but I EDC a Cannon Power Shot SD400 digital Elph and it takes great pictures. It is small enough to put in my pocket and comes with a nice leather case. I've been carrying it for over a year without a problem.

It does use proprietary batteries. I bought two third-party "Power 2000" batteries for about the same price as one Cannon battery. So far they are working great. I get just as many shots as with the Cannon battery.