I want an overnight in a real bed, so I'm willing to pay more to go to podunk-y cities with cheap hotel rates, combining a mileage run and mattress run all together.

Also, it must be a weekend, so I'm willing to pay more for that.

How much? Absolute terms would be a hotel + air cost of (ideally) $350 or less. I'd like to get the best application of miles out of that.