I posted this last year, but it came up again today in class. The US Government set up a Web site where you can enter your phone number, and telemarketers (those people who call and annoy you with sales calls) are supposed to not call you.
Does it work? It has drastically decreased the number of unwanted calls I get.
http://profcameron.blogspot.com/2006/10/telemarketers.html
