JBidwatcher - JBidwatcher is a free eBay tool that's easy to use, multiplatform, and allows you to snipe, bid, and track auctions.
uBuyFirst - Advanced eBay buying software finds newly listed "Buy-It-Now" items first!
Gixen - Free online service that places bids (similar to eBay) in the closing seconds.
Myibidder - Myibidder (Myibay) is a Free Auction Bid Sniper service for eBay.
BayGenie - eBay auction sniping service.
LazyPerks - Keep notified in real time on eBay newly listed BUY-IT-NOW and FIXED PRICE deals.