Ok, I wrote awhile back on a van I am making an entertainment system. I have most of my design worked out, but I need some help and the search both here and on the web has not helped. The concept goes that I would use smart cards to setup a profile of sorts. I have two cards that would set up my wife's or my playlist. I would have a third card that just set up the radio card to play. The problem is coming down to this.

1. I have an idea of using a basic stamp or microprocessor to control the power to different components. The issue here is I have not seen any good examples of using a basic stamp or microprocessor to control power. The finish idea would go like this. When I start me car the proc would get power from the ignition signal. This would cause the proc to send a signal to power up the dc-dc psu. It would have to work not only start, but also the accessories line. The dc-dc would just power up the computer. The computer after powering up and seeing which smart card was in would then send a signal to the proc tell it to just power the char lcd if in radio only, or power on the the screens for full view.

2. I have not found good information with smart cards working with Linux. I have set my mind on Linux due to the ability to have multiple sound cards and video support at the same time using logins.

If you need some more background info please look at my original post @ Need some help with this.