I was looking at MilitaryTimes.com and noticed in a banner ad that Knotts Berry Farm in California has free admission for all veterans and active military on July 4-5. You can bring 6 additional guests for $29.99 each.
Carowinds in North Carolina also has free admission with valid military ID.
California's Great America is also taking care of the troops...same deal as Knotts Berry Farm:
If you see any more deals, post them here!