Ignition Key is a Windows system tray service that allows you to automatically launch applications when you insert your USB drive. It gives you a quick way to launch your most used portable programs and files, as well as a keyboard shortcut to quickly close those programs and eject the drive for you. Install it on all your computers and even if the drive letters aren't the same your programs will launch correctly.

Ignition Key remembers your drives, and won't launch the applications unless you saved it, protecting you from the reason Autorun was removed from Windows initially.