Have you noticed on sellout.woot that when an item sells out, they are replacing it that day?
I noticed this during the woot-off last week that even though they were not technically participating in the woot-off, as they sold out of items, they replaced them with a new item. Same thing happened today, the bamboo kitchen items sold out and now there are batteries being sold.
This is a nice feature, it just makes me have to check the site more often. But you could score if you've already bought something and have the unlimited $5 shipping for the rest of the day.