The Leica Asph lenses are the most contrasty ones. Particularly the 35f1.4 Asph and the 35f2 Asph. The Summilux 50f1.4 is high contrast, but not as agressive as the 35's. The 75f2 Apo Asph is moderate in this aspect. The 90mm f2 Apo Asph is OK, but I never warmed to that lens - performance was a bit disappointing.
The Zeiss line is more moderated when it comes to contrast - but they have one advantage (at least with the japanese built ones) that it is consistent across the board, from the 18f4 right through to the 85f4. The Leica lenses are all over here. I havent checked the latest offerings from Leica to have an opinion on them (18f3.8/21f1.4/24f1.4 and the 24f3.8) but as they all are Asph's, the contrast is most likely bumped up compared to a more conventional lens design like Zeiss/VC.