Yup, my university used Moss and caught a ring of cheaters with it. Funnily enough at my first job I actually worked on a product that was essentially Moss with

Yup, my university used Moss and caught a ring of cheaters with it. Funnily enough at my first job I actually worked on a product that was essentially Moss with a slicker UI, and it would also check online sources such as Github. It worked fairly well, essentially we highlight areas of code that look suspect and it is up to the professor to determine whether it is copied or not. Haven't worked there in almost a year so I'm not sure if the product took off or not.