1 remote for multiple cars???Possible??

[2maximas]

Hi,
I didn't know where to post this so I'll try here.
Anyone ever heard of, or seen a remote that would open multiple vehicles? Something along the lines of a "learning remote" so you could replace the remotes for all your cars with one device? I never have, and doubt it possible, with cars from multiple manufacturers, but thought I'd ask.
Thanks

[SaabJohan]

It should be possible to make such a remote, but very difficult.

The remote/key usually got two functions, to open/close the locks and arm/disarm the alarm, but also to mobilize/immobilize the car.

Each remote/key usually have its own code, and every time the remote/key is used the code is changed. The car must be programmed with all remotes/keys.

So if you want a "multiple remote/key" the hardware in the remote/key must be able to communicate with all cars (varying frequencies and so on), but also programmed in the car. If you got separate remote and key, the immobilizer is probably inside the key so you will still need separate keys.