My bro's a heavy guy as well... ended up upgrading his rear wheel after tacoing the first couple. A bit of info FWIW.

I've been going light research as well. My conditions would be unlit country roads, possibly in a downpour.

On BiFo I've found this one: http://www.shiningbeam.com/servlet/t...h-N3-II/Detail but it's only listed as water resistant.

And a (bike light) tech support guy recommended NiteRider as an all-weather light. Their commuting lights are waterproof to 50m... that gives me confidence. Here's the NiteRider site: http://www.niterider.com/bike.shtml