I started on tophatter.com about 4 years ago when it first came out. At this time, it was mostly people selling all of their gently used items. Now if you visit the website, you will notice it is overrun with independent sellers and shops offering everything from makeup to jewelery!
This is a great way for people who have small businesses trying to get some new sales! I have personally sold almost my entire inventory in just over a month. The only problem is, there are also a lot of spam sellers, who are people that have these computer generated names like "Gtfhvh*******". These are retailers who ship from China. Sometimes what you might think is a "deal" isn't much of one at all!
Overall, I love this site. I visit is numerous times a day and sometimes I even lay in bed at night just watching other people bid. Check it out for yourself and see what I mean!