Gixen

Gixen automatically places your bids on eBay at the last moment.
Entirely automatic - your computer doesn't have to be on.
Group bidding: first successful snipe cancels all the others.
Available for free at the moment, pricing may change in the future.

Important note: I have seen some 1-star reviews with "does not open" message and no details. Please email me at support@gixen.com and include details, e.g. your device. Without you providing some details - I have no idea why it didn't work for you, and there is virtually no chance that will get fixed. Please give me a chance to fix the problem before leaving a negative review.