Vacation in Washington, D.C.!
Youth Hostel
If you really on a budget, you can stay at the AYH Hostel, which is only a couple
of blocks away from the fancy hotel where we stayed.    It's a particularly good
choice for young people, as there are a lot of college-age people staying there, and
they have a lot of activities at little or no cost.
Justin spent one night here (unfortunately, he had gotten used to the cushy hotel).   
Charlaine and I have used AYH Hostels on vacation before, and at $20 a night for a secure room,
they can't be beat.    You do have to bring your own towel, however.
Check out
their website at www.hiayh.org, if you don't have money to burn.