This is my seven segment display that works well even with the BUD switch problem that would usually plague designs like this. The display itself is 3x5 and the piston tape takes up a somewhat larger space behind it. It uses a double pulse on the 20 block long piston tape to get around bud switch problems. I've never seen this concept used before, even though it seems so simple.

You can stack two of them together with only one block in between them. This design could easily be compacted so it doesn't reach back behind the display as far. (I'm lazy)

Enjoy guys!