Vaja is well known for their extremely well fitted, high quality leather cases. Here's their newest Classic case for the Motorola Q. The Classic case is available in a whole range of colour combinations from the Vaja website. You can have the case personalized with various belt clips plus there are a few embossing options.
In order to preserve the form factor of the Q, the case is constructed of very thin leather. It's so thin that it only adds about 3mm to the over all thickness of the Q.