I had a near-death experience last week, when acrid smoke started pouring out of my engine bay while I was cruising at night. Pulled over, rushed out, yanked open the hood, and discovered my left HID was literally burning through the lamp housing...
Turns out my mechanic who installed my aftermarket HIDs didn't screw in the HID bulb securely... it must've got loose, HID filament made direct contact w/the thin aluminium projector housing, and burnt a hole right through it.
At this point, i was thinking "there goes my brand new lamp housing", then my mechanic had a bright idea - to surgically remove the burnt projector lamp cup, and replace just that.
He managed to find a similar projector cup from an old Mazda lying around, ripped my lamp housing apart, sawed off the burnt OEM cup, and mated the new projector cup with the old one (!!). Then glued everything back together. In the pic above, you'll see the new-ish Mazda projector cup... held together by a metal brace to the OEM projector cup from our Insight (or what's left of it, heh)... and the projector lens on the right, with it's socket.
I didn't believe in miracles at first, but hey, it actually does work... my HID bulb sits firmly in place now, and my light quality's just as good as before