EOS-M with a 22mm pancake - it slips in a pocket, it's hidable in less than safe places, it looks like a cheap compact at a quick glance. I carry mine all the time, swap to small jpg mode for work photos, back to raw when I need it, swap to manual focus when light is poor, it's a great little camera that is just with you all the time... Although not quite as handy as my iPhone for quick snaps
I could not have said it better. Thats the way I use my nice eos-m together with my 5DIII and the 7D.