How much are you looking to spend? We were just having a discussion about this in 94-95 and I happened across a link to this HID kit, which I posted for them over there. I'm wondering if the fogs being so low and recessed into the bumper would eliminate the issues typically associated with using an HID kit in a halogen housing?
If you properly aim the lights (not pointing at the sky) the recess and the lens being somewhat translucent really does make a difference, I am able to see absolutely fine using only my fogs ( 04 cobra though) driving at dusk or dawn, although my stock lenses are clear glass, Still though aiming is essential.
before i bit the bullet and went to hid's, i used Silverstar bulbs in the fogs for a while, for some reason they are incredibly fragile and @ 16 bucks each, Yeah... i got pissed about buying those all the time. I went to O'Reilly and bought a set from them in the cheap brand, I think the name was anko?, in an 880 ultra white, i am almost positive that it is the same as a silverstar bulb!, lasted much longer and at 4 bucks. Awesome