[elhigh]

I found one of those little fans you're supposed to roll up in your window, and it would "ventilate" the car. The amorphous solar cell barely generated enough power to turn the fan, let alone move any air. If you're going to do it, roll your own and make sure to lay out enough panel to really get some breeze going.

I get decent results just leaving all my windows cracked and a big piece of cardboard in the windshield. It'd be great to achieve better, but my $0 investment is tough to improve upon.