Apple’s iPad case seems to a populate choice – hardly surprising given the multiple positions it allows you to use the device in – but Amazon is now listing a number of alternative leather cases for the device including this one from Tuff-Luv or this writing pad-style folder
Those happy to shell out a bit more may like this Marware Eco-envicase which is a made from “leather with contrast stitching and an environmentally-friendly fleece interior make the leather envelope attractive and practical” and “designed to allow you to use in conjunction with other thin shell cases”
If you’re looking for something a little more fun there’s a host of silicone cases such as this rather shocking pink one or this mildly less eye-killing blue option which includes a screen protector – though personally I’ve never found those screen protectors much help or use.
There also some neoprene iPad bags available but few seem to list protection for the screen side of the device among their features.
I suspect I’ll wimp out and stick with Apple’s, not least because the typing position configuration could really come in handy for typing longer documents.