ive done about every mod there is with the exception of multiple cells, which will be arriving soon. it will be a layman's 3.6v tri cell mod. it should be 'tony-proof' hehe. even *I* can change a battery
lets see...
i can:
*put a custom spoiler on a zip that shouldn't have one, IE the porsche or mustang or pt cruiser
*lower cars (but you have no problem doing that already, nice job by the way
*change the antenna, make it a piggy tail kinda one
*put a 3-4ft antenna in the controller
*set the controller to direct charge, which takes off the timing limit of a stock controller and gives it more juice (as i was typing this, ironically i left it on the charger too long and ruined my battery
learn from my mistake lol)
*double tires so you have 2x wider tires in the rear, front is possible too, but will require dremmeling
*rare earth magnet mod
*paint rims
*and a few other things that dont come to my mind right now