What is Your Camera Case for S100

I recently bought an S100 and would like to get a case for it so that it can be placed in my wife's purse or a beach bag.  Therefore my preference is for a case that zips up completely so nothing can get into the case to scratch the camera.  I also prefer a fairly snug fit so that it doesn't add a lot of bulk.

If you have a case that fits this description please state the make & model and why you happen to like it.  Similarly if you found some I should stay away from, let me know as well.