A free, lifetime pass - available to U.S. citizens or permanent residents of the United States that have been medically determined to have a permanent disability - that provides access to more than 2,000 recreation sites managed by five Federal agencies.
A permanent disability is a permanent physical, mental, or sensory impairment that substantially limits one or more major life activities, such as caring for oneself, performing manual tasks, walking, seeing, hearing, speaking, breathing, learning, and working.
http://store.usgs.gov/pass/access.html
I had been paying the annual fee for a few years until I realized I qualified for the access pass. No need to be shy about applying.
There is also the Senior Pass
U.S. citizens or permanent residents who are 62 years or older. (You must have turned 62 before you can buy the pass).
A $10.00 lifetime pass that provides access to more than 2,000 recreation sites managed by five Federal agencies, with up to 100% of the proceeds being used to improve and enhance visitor recreation services.
http://store.usgs.gov/pass/senior.html
