Buy year passes for state and national parks

Even if you aren't going to be going more than once or twice, buy a full-year pass to your state parks (usually around $25), or a national parks pass ($80). That money goes right to the park system, which rely on taxes (which are never enough) and these passes for funding. Our state and national parks are an incredible resource.

Here's a link to my favorite state park, near where I grew up: http://www.mostateparks.com/rockbridge.htm