Groundcloths - again

I'm thinking of geting a Cuben fiber groundcloth in 3/4 the length of my tent floor. It seems to have the lightest weight for the the strength.
Someone please enlighten me on what's available.

1. Is there a waterproof Cuben fiber?

2. If so what would be the lightest W/P Cuben fiber cloth available?

3. Does this stuff come in colors other than white?

UPDATE: I read Ron Bell's (of Trail Designs) post over on BPL & it appears the strongest nearly puncture proof Cuben fiber is called "CN2K .08" so I'll see if Seattle Fabrics has it.

Any other sugestions?

Eric
BTW, I want it for my new Moment tent to save the floor. OF course that fiendish Henry Shires will invent another, more clever solo tent next year and I'll have to trade up to it and the Moment will have seen only a season's use so why even bother with a groundcloth?

Why not use the polycro ground sheet from Gossamer Gear? Do they still sell it? Very light, amazingly puncture resistant for the weight, and waterproof.

I just checked and here it is.

http://www.gossamergear.com/cgi-bin/gossamergear/polycryo_ground_cloth.html

why not just use Tyvek as a ground cloth?

The Polycro sounds good. Been using Lowe's painters drop cloths but it appears the Polycro is tougher. I'll try it.

Tyvek is very light and very tough but, in my experience, it picks up too much dirt and is not entirely waterproof under pressure.

Eric

Someone on BPL is trying to put a big order of green cuban together. Pricy stuff.

Exactly my feelings. Why bother? Just totally useless things, even on ultralight tents.

BF