I agree - it's a great tool. You can make many sizes as needed - so don't have to keep packages of strips of varying sizes about. When I worked on Bonnie Hunter's quilts and needed literally 100's of HST's, this was fabulous!
I buy doodle paper at the Dollar Store, trim it to printer size and run it through. Much cheaper than the packaged foundation paper, and much easier to rip off than copy paper.