Of course, I don't go to this site alot, so I don't know how reliable it is -- this article was pointed out to me by a co-worker.
quote: Microsoft has been granted a patent on the double-click by the US Patents and Trademark Office. The patent, number 6,727,830, was granted on April 27.
It should be noted that they're not patenting the double-click; they're patenting the idea that launching an application with a double-click will bring up the application in a different mode than single-clicking will.
Ridiculous, of course, but not the most egregious I've seen. Here's a fun one:
Also, someone tried to patent a construction cost estimating algorithm that relied on the application of factors to various parameters. In other words, estimating construction costs based on average price per square foot.