Reading through the RFC's can result in finding very interesing and important topics that any sysadmin would deem useful. I also sometimes find it to be a good cure for insomnia reading through it, and some RFC's are just down right bogus (RFC 2795: Infinite Monkeys).
Just like in college, I know how to push through some of less exciting material by a good strong cup of joe. But I would like to know which RFC's are worth spending $5 on my triple venti caramel macchiato?