yeah, I used it. It was a dumb terminal with something like a 1200 down/110 up baud.... Later ones were in color. Basically, it was a little box with a tiny screen you plugged into the phone. There were a series of telephone exchanges dedicated to the Minitel (3615, 3612, the whole 36xx series probably). You'd type in "3615 SNCF" for example, and it would connect you to the national railway timetable and reservation system.
3615 ULLA was for men and women looking to get laid. My gf at the time had a friend who used that, and from her description, he got some pretty impressive scores.
I used it predominantly for train schedules, airport information and occasionally as a phone book
As of 5 years ago, Minitels were still around.