Here's a product that might interest you
 

I have been looking for a emergency seat cover for the drivers side of my truck to keep sweat, mud etc. off of it. Found a product that is great, it is a thick terry cloth towel and is sewn to a piece of gortex material. It is custom hooded so it fits over the top of your seat and has ties on the back. Follow the link below for info. on the cover. It looks much, much better than the pics show, I'm going to leave mine on all the time since my truck is for work as well as pleasure. She will make it to any size and color you want. I have gray interior so I went with a gray towel material and black hood gortex material.Ask for Bridgett and tell her Bill sent you.
http://www.dryspot.com/truckseat.htm

I'll stick with my custom seat covers!
 

I recommend that if you want to protect your seats you just go ahead and invest in seat covers. I got custom seat covers for my '00 Lightning Short Bed and they fit perfectly, match my interior perfectly and protect my seats like a champ. They are a denim material, not that cheap looking wool crap. I got them from www.seatcoversdirect.com IMO, it makes sense to just go ahead and have seat covers made because they don't look like a cheap fix.

John

Well unfortunatly I have to use my truck for work as well as pleasure. I'm in the construction trade and seats as well as seat covers soak up sweat and get a little smelly. With this it can be easily removed and washed and put on only when you need it. I have had it for a few weeks now and I think it's great.