I have a Priceline room in Mira Mesa at Homestead Village (2*) for $30 a night (plus $5 bonus money) for Thurs, Fri, Sat. This is 17 miles out from the airport, but worthwhile for me. Bid on other San Diego zones without sucess at this price, and added it on as my last option. I'll have a rental car, as I have some friends that work in and around San Diego I want to catch up with this weekend, too.
I've previously stayed at Homestead Village at BWI and it will be just fine for my needs.