What algorithms are patented?
The best overview I know of on this topic can be found in the comp.compression FAQ. You can find the comp.compression FAQ via a link on my FAQ, follow the links from my home page. comp.compression and comp.compression.research sometimes will turn up answers to questions regarding specific techniques, but the murkiness of patent law makes it hard to trust *any* source of information. Finally, to see the body of these patents, IBM is doing a public service by keeping a giant database of patents onlline. You can reach the IBM patent server at: http://patent.womplex.ibm.