There are quite a lot of old-school BBSes configured for telnet access.[1] There's even a telnet/SSH client called SyncTerm [2] that emulates old terminal modes with authentic fonts.

There's also a site called Telehack that's an attempt to simulate what the internet would have been like for the typical user about 25 years ago - pre-web.[3]

There's a lot of stuff like this out there that satisfies itches for nostalgia, creativity, and an open frontier all at once.

[1] http://www.telnetbbsguide.com/

[2] http://syncterm.bbsdev.net/

[3] http://www.telehack.com/ (or, for a more authentic experience, telnet in with SyncTerm)