Here is my tall bike:
The bottom frame is an old Fuji which is at least a 60cm, the top frame is a Peugeot which is a 56cm, I believe. So the bike as standing in the photo measures about 6' from the ground to the seat, considering it is rolling on 700c wheels.
I wish my friend and I hadn't built this thing so hastily, because we made a huge mistake while extending the fork - we just cut the steerer tube off completely and welded some EMT conduit to the fork crown. So now this beast has no headsets on either frame, causing the 3/4" conduit to shake violently in the head tubes when you ride. It's tons of fun!!!
*edit - sorry for the non-driveside photos.