Looking for any Detroit Boomers who remember The Pipeline from the 1970s. I spent my grade school years in Oak Park, but I think it was also available in Southfield. Basically, if you dialed any of several 3-digit numbers [[511, 211, 711 were some of the combinations) you'd connect to what was essentialy a voice chat room and talk to a bunch of other kids or teens. This wasn't a commercial service or anything like that, it was something kids stumbled on accidentally and then spread via word of mouth.

I haven't been able to find anything about this elsewhere on the web...