Michael sent us news of yet another iPhone case, this one made by Noreve. It looks pretty nice, and it's interesting that they created a flip that goes down instead of up-- they say that the camera is still usable with the case on, which is super nice. The colored cases aren't selling yet, apparently, but the black cases are in stock at €42.99.
And while my personal choice is probably to go with one of those cool wooden cases, if you really want leather, you'd be crazy not to take a look at the Vaja cases. Like TUAW's Dave Caolo, I've got a nice one on my iPod, and it is excellent. Like the Noreve cases, they're a little pricey but if you're going go all out and buy an Apple cell phone, you might as well go all out on the case, too.