I remember one particular student-led seminar from my university days, where one guy had his art student missus fake up some modern abstract art, then showed them on slides along with some originals. We were then asked to judge which was real and which was fake, and how much each was probably worth. The idea of all this was to prompt discussion around this very topic.
We came to a 'Terry Frost' and couldn't decide - even the lecturer (a past curator of some pretty influential collections) couldn't say. When we talked about value the lecturer said, "well, if it is a Terry Frost, then it would be worth a lot of money indeed." In the end, it turned out to be a fake, and I daresay an art expert would have been able to tell the originals apart, but it was an interesting seminar.