Google Patents Sketches

If you like sketches of product designs, and things people patent (often very odd), I recommend Google Patents search. For the product designer, these sketches are often educational as effective communication tools.

Warning: Most software companies don't want you doing any patent searches on anything you work on, because it can get you in legal trouble if you have prior knowledge of existing patents when you produce new designs. So avoid searching on patents related to your current software design work!