I think the various freenets have been around since early 1990/1991. They started off with free shell accounts for accessing email and usenet.
Here's a list (circa December '93) which shows the large # of freenets already operating by that time:
http://archive.ncsa.uiuc.edu/Edu/ICG...tml#freenets11
I think I signed up for my first "Internet" account with the Prarienet back in 1990.