I am not at all sure what you mean by "mattress run"!. The usual meaning is a series of stays at chain hotels (e.g. Hyatt, Hilton. etc.) with the sole purpose of accumulating points/stays and/or status in the chain's reward program.
If you are just looking for a cheap hotel for weekend get-aways,there are a number of options. I suggest that you start with Hotwire.com and then try Priceline