yup, it's been done. Silverstars are about the best you can expect without going HID.
In a couple of weeks I am going to check out someone in the North Bay that installed 8800K Stage 2s...should be interesting. I will bring my shades.
Sylvania just came out with a few totally legal HID systems for as little as $500. The problem is either you buy one as a custom fit for Ford 150 trucks, or you have to buy it as supplement lamps to add to your car. No 9006 plug ins!!! That sucks!
(these are st. 1's of course).