I've used the Ricoh GR1s and love it. It's very compact and easily fits into a jacket pocket. It's very discreet for shooting in the streets and pretty fast w/ a f/2.8 lens. It's pretty wide at 28mm. But now that we are moving into winter, I'm looking for a Richoh GR1v that will allow me to push/pull 3200 speed bw film with its manual ASA control. Will probably sell the GR1s if I can find a GR1v.
I should also mention the 2 Olympus camera models I use that are very small with good glass: the XA3 and mjuII (Stylus Epic). Both are 35mm. The XA3 is very quiet w/ a f/3.5 lens. The Stylus Epic (my every day carry camera) is fast at f/2.8 and is the most compact I own. I actually own 3 of this model I love it so much.
Hope that helps!