personal preference. I once worked at Winder Boats in the UK and they used a yellowish looking polish, but I'm not sure what it was. I also have a Mirror though and I used a very slippery carnauba wax on that, but i don't put anything on my Laser
A couple of the more expensive solutions
Rain-X - This was pretty common at the Olympic trials in 84 when I was sailing a Finn
Sailkote - I'm told this has been used lately.
I think they both basically work the same way, a hydrophopic coating.