The small tower on T1 is used for Apron Control. I was up there in 2005 for a Y11 work experience. The view is pretty good but you are restricted on T3 due to the angle.
It has two levels, the upper level consists of a semi circle of monitors and seats with a whiteboard behind you which is used to decide on which a/c to be on which remote stands overnight. Above, suspended from the ceiling are monitor showing all flights and the assigned gates, similar to what is found in the Control Tower.
The lower level mainly has filing equipment and cabinets etc. There is still space to move around though. Its a great spot to work in. I would love to work in Apron Control but i still can't find a suitable contact for MAN.