"You may request a waiver of fees. Under the FOIA fee waivers are limited to situations in which a requester can show that the disclosure of the requested information is in the public interest because it is likely to contribute significantly to public understanding of the operations and activities of the government and is not primarily in the commercial interest of the requester."
Also, regarding fees, I really don't expect that the NSA is going to respond to your FOIA request without a fight, so I personally think it's a non-issue. The idea here is the protest, not an expectation that you'll actually get your records!
Sounds like that applies to most everyone to me!