Not leaves, but I find the roots of chiloschista very cool. Spathoglottis has cool leaves too, similar to a screwpine. Ludisia is nice too. Mottled paphs are also good.
Amazing...I seem to be saying that a lot lately. Source for that?
Ebay. I actually just got it yesterday. I think there are a few more. Watch that vendor though, you need to BEG for a heat pack, and she charges like 2X what the rest charge!