There are a few sites I check daily or at least weekly.  These sites have great deals and give an opportunity to save some dough on occasion.  Please list any of your favorites not listed in the comments section.

Woot
They have one item a day, that’s it.  Occasionally they have a “wootoff” which is when they clear remaining inventory at  ridiculously low prices.  On “wootoff” days they have several items throughout the day.

1saleaday
This site is similar to woot, but they have several different categories of items.

Amazon’s Gold Box
We do the majority of our Christmas shopping at Amazon.  The link I listed has one item discounted all day, and other items throughout the day.

Musicians Friend Stupid Deal of the day
I buy almost all sound equipment, cables, and lighting gear from Musicians Friend.  The link is for their daily “stupid deal.” 

Newegg
If you are looking for electronics, go to here.

Goodwill Auctions
This is the new auction site for Goodwill.  Some great deals can be found, and not too many people know about it…yet.

Hip2Save
This is a new one for me, but there seem to be some great ideas, coupons, and even freebies here.