I'll probably get hip dysplasia from sitting on my bulky leather wallet. I've been looking into getting a slimmer wallet for this reason, and the Ebax Bifold looks like a nice alternative to sitting on a hunk of leather.
For starters, it's made with microfiber and is water resistant. It's got RFID signal-blocking, and it's incredibly thin, at less than a quarter of an inch thick.
The wallet has gotten solid reviews from Amazon customers, too.