Since every patent is required to contain an abstract section which summarizes the invention in the inventor's words, reading through a patent's abstract is a good way of getting a sense of what the inventor regards as his invention.  Additionally, reading through just the first patent claim, which tends to be the broadest, is an effective way for getting a sense of how broad a court is likely to interpret the patent since, as mentioned earlier, courts will generally limit the breadth of the patent to what its claims recite, regardless of what the rest of the patent purports to cover (although there are a couple of exceptions to this general principle).  The patent summaries listed below are required reading, but concentrate mainly on the abstract section and only skim claim 1 of each patent.  The links to full patents are supplied only for the courageous.

Priceline.com

A patent on the "name-your-own-price" business model that lets consumers indicate how much they will pay for a specific item.  This patent was issued to Priceline on Aug. 11, 1998. (Patent No. 5,794,207) - [Patent Summary] - concentrate only on the abstract section and skim claim 1 of the patent.   [Full Patent] - Optional
 
 

MercExchange

A patent on a way to allow bargaining after purchase of used or collectible goods by computer "in an electronic market."  This patent was issued to MercExchange on Dec. 1, 1998. (Patent No. 5,845,265).  Thomas Woolston, the inventor of this process claims this patent covers Priceline’s model. Although Priceline’s patent issued first, U.S. patent law is based upon a "first-to-invent," rather than a "first-to-file" or "first to issue" system. [Patent Summary] - concentrate only on the abstract section and skim claim 1 of the patent.   [Full Patent] - Optional
 
 

Open Market

A patent on a network sales system which potentially covers all versions of e-commerce was issued to Open Market on Feb. 3, 1998 (Patent No. 5,715,314). [Patent Summary] - concentrate only on the abstract section and skim claim 1 of the patent.   [Full Patent] - Optional
 
 

Double Click

A patent that covers the process of delivering customized advertisement over the Internet, based on consumer demographic information and the like.  [Patent Summary] - Required (concentrate only on the abstract section and skim claim 1 of the patent).   [Full Patent] - Optional