smartphone apps

[0X01B8]

I want to start working on making applications for smartphones (Android, iPhone, Blackberry, etc) and hoped to get some ideas from you guys.  You might know me from my prior work, which you can see from the unobtrusive link in my signature below.

I'm hoping for some ideas for apps that you might want to use while you're in/on/driving/racing your car.  Otherwise, why would you want it on your phone?  I have some ideas myself but they're a little advanced, considering that I have yet to make an actual app.  No idea is too silly.
thanks.