I'll be following this one, I'd love to get a scanner for the truck but they do seem complicated for mobile operation. I use the ham for scanning analog FM on VHF/UHF sometimes when I think about it, pretty cool monitoring the fire dispatch and park ranger animal reports in national parks. And I actually ended up joining OB because I stumbled across a group in Alabama Hills last year by scanning FRS/GMRS and joined them on their Death Valley run.
It would be cool to get digital trunking, P25 etc going for emergency services, but I have no idea how all that works or if it's feasible to mess with while mobile.