You've seen this before, no doubt
But still worth commenting on.
Woot goes all the way to the edge in that they sell just one product a day. This is extreme (about a millionth the size of Amazon) and very effective in attracting your interesting and spreading the word. What could be good enough or cheap enough to be the only product of the day?
The second thing they do that's neat is that they support RSS. Which means you don't have to remember to go there every day. You can subscribe. I love subscription-based businesses.