A large number of readers wrote in about IBM suing Amazon over commerce patents. The Ars Technica coverage linked is one of the few sources that goes beyond the brief AP or Reuters stories that everyone is running. Here is IBM's press release. Some of the patents in question go back to the 80s and they do seem to pretty much wrap up the idea of online commerce, if they prove valid. IBM says many others are licensing the patents but Amazon won't give them the time of day on the subject.