A configurable "key" for use with vehicles. The key would be based on a USB flash drive that could be configured by the owner of the vehicle. Any flash drive could be used and configured by the owner.

Possible applications:
1) Fleet or rental agencies that could set an expiration date or time based on how long someone had rented a vehicle for. Once the time expired, the vehicle could no longer be driven.

2) Parents that want to restrict the hours that a vehicle can be used or the top speed at which it could be driven.

3) People that have multiple vehicles and don't want to carry multiple keys. Multiple vehicle profiles could be loaded onto a single flash drive.

The owner would have software on their PC that would allow them to program the device and create user profiles. Because a standard flash drive is being used, no special cables or adapters would be needed. Each profile would be encrypted and synced to the home PC and software, thus preventing unauthorized duplication.