At Virginia Tech
, stands for Fuck the Corps
The Virginia Tech Corps of Cadets is the military subset of the student body. They live in separate dorms, wear uniforms to class, perform drill, and pretty much live as if they were in a military school. The culture clash between civilians and cadets, though, is rather amusing, and sometimes leaves Corps members wishing they weren't so restricted. Hence, the popularity of FTC amongst the Corps members.
Of course, it's rather popular among those who have quit the Corps for whatever reason, too.