I have an old computer that still runs great but can't really be upgraded to new OS, etc. Just for fun I set up a nostalgia ansi dialup BBS on one phone line. Contacted all my old BBS buddies and said "have fun!". They did. And over the last two years the BBS has managed to accumulate a 40-45 user base in the local area who are willing to defray the phone line (basic service, inbound fixed, metered outbound... I do no outbound!) and 100 or so more new visitors each month, most of whom giggle, have a little fun, then never return. The BBS runs a message board, code board, news board, no files. This is truly "local" connectivity. I also offer what's left of Fidonet, too.
Not getting rich, but is costing next to nothing, promotes goodwill, and is a grand trip down memory lane for all of us who lived and breathed CP/M, DOS, and OS2 back in the day.