I've been using eSnipe for several years now. I still remember the "good old days" of staying up late, putting in bids in the closing minutes, heart racing, spending more than I intended....
My favorite thing is their SnipeIt! tool. You download it and it shows up in your "links" in your toolbar. When you're on an eBay page that you want to place a snipe bid on, you just click the SnipeIt! link and a pop-up window automatically takes the auction information from the page you're on. You tell it how much you want to bid and that's it.
Bid groups are cool, too. If you wanted a particular item, like a certain movie title, you can put snipe bids on multiple auctions for the same product. It will submit your bids for each auction but once you win one it cancels the rest of the bids in the group.
The fees are reasonable and well worth it. This is definately one to check out!