Other things to do -
1) tour Colonial Williamsburg - although that's definitely not 'budget minded'! If you opt not to purchase tickets, there's still plenty to do. You wan wander around the grounds of the buildings, go to the Visitor Center, etc. without a ticket. See
http://www.history.org for more info.
2) Merchant's Walk - great little shopping area, mostly boutique type stores, many high-end but a few little privately owned shops have reasonably priced merchandise
3) Busch Gardens/Water Country - there are always discount coupons floating around for those at fast food restaurants, grocery stores and on soda cans
4) Virginia Living Museum (Newport News) - this is a great place to take the kids, relatively inexpensive as well
5) Virginia Beach - you're only about 1 to 1 1/2 hours away, depending on traffic
6) Richmond - TONS to do in Richmond; about 45 minutes away
7) Miniature golf - there's a really fun looking course right off Route 60, at the Bypass
8) Outlet mall shopping - need I say more?
9) Jamestown Settlement/Yorktown Victory Center - if you'd like a dose of history but aren't ready to cough up the big bucks for Colonial Williamsburg, consider this instead. See
http://www.historyisfun.org.
10) Plantations - there are quite a few plantations in the area between Williamsburg and Richmond. Just taking a drive to look at them all is really fun, and many are open for tours.