sooner said:
These dSLR's just aren't small any way you slice it, and the pancake lens won't change that.
OK, let's compare:
Pentax K100D: 129 x 93 x 70mm
Leica M6: 138 x 80 x 38mm.
So the dimensions aren't
that different. The width of the Pentax is actually less. The Pentax's added height mainly comes from the SLR bump in the middle (
picture), so in frontal view it's not as massive as the 13mm difference suggests. The Pentax's added thickness comes mainly from the grip and partly from the mirror box housing. The mirror box can be compensated for by using a slimmer lens, such as the aforementioned Pancake (
picture). The grip isn't that dramatic as it looks because it nestles into your hand, and many Leica photographers use a grip like Tom Abrahamson's, too.
A typical Leica setup like in
this photo.net article with grip and external finder is not much smaller in the overall dimensions than a DSLR with a small lens, which has the grip built in and doesn't need an external finder. (A little anecdote: some three weeks ago I sat at a table with some photographers here in Berlin. One of them had come visiting Berlin and took pictures with an M8. Everybody had their cameras on the table. The M8 had the quite ugly Leica grip and the huge wideangle multifinder more or less fixed to it, because one of his lenses was the wideangle Tri-Elmar and didn't want to change finders along with the lenses. All in all it wasn't a small camera, and when he mentioned how he preferred rangefinders because they were so compact, he met with a lot of raised eyebrows, because he had the proof to the contrary right on the table.)
So anyway I think the size advantage of rangefinders is a little overrated; if you
want a small SLR, you will have little problems getting one.