I use cash for almost everything. Usually keep a few grand on me just in case. Never know when a truck needs a $500 tire while on the road, fuel ($4 gal), etc.
Well you could by paying yourself with a credit card and using that $$ to pay the mortgage. Would have to get setup to accept credit cards, and then around 3% few so on a 1500$ house payment it would cost $55. Probably more than any points are worth.