The Tile is a tiny plastic widget that never gets lost. In theory anyway. It talks to your iPhone via low-power Bluetooth and lets you track the Tile itself, and anything the Tile is attached to.
I’ve been using one for the last couple of weeks, and it works just fine. But so far it doesn’t seem to be much more useful than one of those keychain finders that beeps when you whistle. Why? Because to be truly useful, the Tile needs to reach a critical mass of users.