Myibidder is a Free Auction Bid Sniper service for eBay.
The service supports groups (when you want set your snipe on several items and want it stop after you win some certain number of it), different eBay International sites, eBay motors.
When you add an e-mail to your profile, you will be getting e-mail notifications on the snipe status.
If you go advanced, you can get a Windows client software which help you to manage your snipe items and groups.
iPhone/iPad app and Android app are also available for mobile platforms.
Although, the service is completely free, the client software is not. The proceedings from the sales of the software help to keep the service free.
The software supports English, Dutch, French, German, Italian, Portuguese, Russian and Spanish.
There is a free Firefox and Google Chrome add-ons available for easier adding an item to your list of snipes.
The general disadvantage of online 3rd party snipers is that you have to give your eBay password information. However, you can always register a brand new eBay account and use it for sniping only so it will not be linked to your financial information and keep your primary account safe.