Another quarterback of note would be Danny White. Played at Arizona State and then spent some years with the Dallas Cowboys. The offensive lineman from Africa (actually I think he was from Canada) that somebody mentioned previously was Mo Elewonebe. Mo won the Outland Trophy while at BYU and then went on to play for the Washington Native Americans. Another defensive end not mentioned would have to be Brett Keisel, now a starter for the Steelers. His counterpart while at the Y, Denney (I think John was the first name), would be another worth mentioning.
On a related but side note, does anybody else find it ironic that perhaps the two best defensive ends to ever play at BYU, along with stong safety Aaron Francisco, were part of one of the worst defenses that I've ever seen?