According to Wikipedia, the term "woot" means the following:

"A slang interjection used to express happiness or excitement, often expressed via the Internet."

Woot.com’s daily updates are engaging, humorous, and they even offer good deals on electronics. During 2006, Woot has played host to an average of 130,000 thrifty people a week by offering one product per day at a significant discount. Yesterday’s woot, for example, was a quality DVD Recorder selling at a close out price.

It is not requisite, however, that the featured product be an electronic device. From time to time the offering will be a "Bag O’ Crap" (or "BOC"), which is simply a grab bag of 1 to 3 mystery items. Most people will get what they pay for (one $ per item) but a few lucky recipients will be blessed with some electronic product that is certainly worth more than what they paid. Believe it or not, every last BOC usually sells out within minutes of being posted. Woot.com’s business plan of offering only one item per day has established them as the homepage of many a blog reader throughout the US. It takes a good blog to know one!