If you're using white or black paper there's something my friend Jeff Black turned me on to a while back that has worked pretty darn well...
Go to Home Depot and buy 2 4X8 sheets of something called "tile board"(I think that's the name) It's usually in the section with paneling. This is a fiber board product with a white enamel type surface on both sides. Grab a couple of cans of black spray paint(gloss).
Paint one side of each panel black, taking care not to let the paint drip over to the unpainted white side.
Now when you shoot, unroll your white or black seamless paper and then lay your new "floor panels" down on top of the paper.
This has worked well for me. Occasionally you have to clone out the seams between the two floor panels with Photoshop and very rarely do you ever see the edge of the back floor panel separate from your paper. This technique saves oodles of Seamless paper. I've been doing this for 2+ years now and only just last week did I buy a new roll of white and black paper. Of course, when shooting with colors other than white or black, this solution isn't the cure all obviously.
Hope this helps.
