I wrote an assembler program for my TRS-80 model I (z-80) and ran a small BBS with a single 300 baud modem which I built for about a year.... a long time ago. Just my friends basically used it. I had to build my own auto-answering circuit... that was fun.
Later on I ran a "galacticomm" BBS for a while, I wonder if they still make those things.
Now I just program applications and websites. Much more effective than a dialup BBS system.
:)
-Dave
www.GalleryDir.com