sweetheart used his keyboard to write :
They used some last minute bidding software - try Bid-O-Matic. If you cannot beat 'em, join 'em.
You fill your ebay details into it, so it can bid on your behalf. You then test it against dummy ebay items set up for the purpose, so it can see what the Internet delays are.
You then enter the item number and then the highest price you are willing to pay for the item. The software then waits until the last few seconds, watching the bids and makes its own bid - just enough and no more to beat the last price it sees. Sometimes it wins, but not always. You can set up several such bids grouped, on similar items, so you would only win one such item - the first one upon which it makes a successful bid, then the rest are ignored.
I believe ebay has such a last minute bidding option built into it, but I also suspect your bid is fixed at the amount you enter, rather than just enough to win the auction.