You might want to check out Karen Nakamura's equipment page. In particular, she's got a page devoted to wide angle LSM lenses. She likes the Jupiter 12 that Gordon mentions, but with some rather important caveats. (A tip: A Kodak plastic film can, cut to be a bit shorter, makes a good rear lens cap for the Jupiter-12. Other brands of film can aren't quite the right diameter.) I've got a Jupiter 12 but I seldom use it because I change lenses frequently, and that's awkward with a rangefinder, so I end up using SLRs more often than my two FEDs. I haven't used the Jupiter 12 often enough to really evaluate it properly, but my initial impression is positive. OTOH, I've got FEDs, so I don't have the problems that are mentioned on the page I referenced.