If you're interested in what it's like to use a BBS in the 21st century, as opposed to back in the day, check out the new BBS Documentary series called 'Back to the BBS':
https://www.youtube.com/watch?v=n0OwGSX2IiQ&list=PLop3s1hMlS...
It's a multi-part docu-series with interviews from the most active and interesting people from the scene, covering the following topics:
INTRO TO BBS’s
GAMES / DOORS
MODS
HARDWARE
BBS SERVER SOFTWARE
BBS MESSAGES
PRIVACY
ANSI GRAPHICS
DEMOSCENE / MOD SCENE
THE UNDERGROUND