Headlights - I wetsanded mine with 1000 or 1500, then PlasticX, came out great.
Here's a thread with several different suggestions and results.
http://www.vehicross.info/forums/sho...+sandpaper+wet
After you get them cleared up, you can also use 303 with it's SPF 40 for UV protection, or Plexus (but I don't think it has an SPF). It's the UV rays that caused them to haze up in the first place.