It was the general student computer at the University of Minnesota, and the uses it were put to were all over the map. Despite being optimized for number crunching it was an amazing general purpose computer.
The most interesting architectural feature was that all I/O was relegated to peripheral processors so that the main CPU could run unimpeded.
I think UCLA had a CDC 6600 being used as a time share system. My memory is very hazy though. We used it remotely via 150 baud terminals. On hot days occasionally bits would get scrambled on the way there and back.
10 PRINT "YOUR MOMMA" came back as 10 PRINT "KOUR IOMMA"
The most interesting architectural feature was that all I/O was relegated to peripheral processors so that the main CPU could run unimpeded.