I need to re-waterproof my cockpit cover. What should I use?
Id like to pick up something tonight at Boater World or West Marine on the way home.

Head to you local fabric/craft store and pick up two bottles of Igloo Waterproofing. It is in a small white bottle witha purple lid if I remember correctly. You throw it all in the washing machine, and it comes out perfect.

I bought my stuff at Boat US. It was just called Fabric Water Proofer(I believe it was their brand)and it came in a gallon bottle. I used one of thos bug/lawn sprayers and it worked. I hear Excellent things about 303,I just have not used it yet.

Sydwayz
Do I through this in "my" washing machine or should I bring it to one of those commercial coin opperated deals?

Commercial

I did it at home actually, but we had a decent sized washer; and I was renting.

I used the same stuff as 1boatnut, waterproofer from Boat U.S.
The stuff works great.

I layed down plastic painter's sheets on my driveway and duct taped it down. On that I layed my boat cover.

I just dumped the whole gallon into a bucket. I used a nylon brush on a long handle to apply the sealant. It soaks up quick, You'll be surprised how much you'll need.

After I spread it out between two sawhorses and it dried in 30 minutes.

This worked great as the sealer actually got 'into' the fabric throughout. Not just a surface coat from a sprayer.

Do that once or twice a year and you'll be all set.

Look in the yellow pages for carpet cleaners supply house. Go and buy a solvent based protectant for upholstery and carpet. Usually in the $30-40 range per gallon for brand names and its ready to use. Works great. You can also find the water base Scotchgard or Teflon at those stores too, but you have to buy in bulk, 1 gallon that makes 5 gallons for $40 - 50 range. Make sure your cover is clean and dry before you apply and use a pump up sprayer.