Another great idea that's spoiled by being far too dorky, the CoolCop is a personal air conditioner for the gendarme-on-the-go. A tube hooks up to the car's air-con vent and pumps cool air into a vinyl undervest. It looks terrible but the testimonials on the product site say it works great:
The tube fits any standard 2 1/2" A/C vent, and comes in at just $50. The vinyl undershirt is a worry, though. It might be cool when hooked up, but could be a real sweatbox out in the midday sun.
Poking around the site, I found another little gem: The CoolK9, a similar system to cool police pooches. The same hose routes cold air into a dog kennel. Awww.
Product page [CoolCop via Neatorama]
Product page [CoolK9]