Possible uses:
"Party interrupt lever"
"Dietary science"
"Crowd control"
For the first, install the peepshow booth inside the statue gardens and dining halls. Link all devices to a single lever. Any time you get the "X has organized a party at Y" message, throw the lever, wait a few seconds, then throw it again. Party cancelled.
For the second, I have already stated the intent.
The last is a little curious... say you have an area of the fort that you need to keep pathable, but want to keep dwarves out of. Installing the peepshow booth with dancing skeletons inside will make dwarves cancel whatever they are doing in proximity with the booth, while being perfectly safe otherwise. This can keep dwarves away from dangerous locations, assuming you have dealt with the issues of "saw the undead" thoughts contributing to fortress wide neurosis.
The normal peepshow booth system poses a significant risk of atomsmashing friendlies, so a little modification to the design is in order:
O÷÷÷÷÷÷÷O
÷_________÷
÷_OBBBO_÷
÷_B÷÷÷B_÷
÷_B÷N÷B_÷
÷_B÷÷÷B_÷
÷_OBBBO_÷
÷_________÷
O÷÷÷÷÷÷÷O
It's a little bulky, but installing it inside a hallway intersection would render the hallway essentially impassible to dwarves on demand, since they would see the zombie and cancel their current pathing job, and run way. The outer ring of fortifications allows LoS TO the zombie, but prevents pathing on the "smashy" floor tiles, allowing perfectly safe operation of the booth. Such a booth could be installed decoratively inside the legendary dining hall, and in the statue gardens quite easily.
(Key:)
O == wall
÷ == fortification
B == raising bridge
_ == floor
N == zombie
I normally don't include the outer ring of fortifications, since I put these outside, and put syndrome secretion spewing FBs in them, and if gobbo mcgoblin decides to stand on the smashy tile, well, one less body to clean up.
Being "on/off-able" like that means such a feature could be used quite inventively.
An improvement on the design would put a walled in necromancer directly above the zombie chamber, standing on a floor grate floor. That way, if Urist McMarksdwarf decides that seeing the animated skeleton of his dearly departed aunt ducim is just more than he can handle, and opens fire and kills the zombie, the necromancer will immediately see the corpse and raise it, while being safely out of LoS from the marksdwarf. Getting necromancers in sufficient numbers may prove problematical without using Embark! on top of a necro tower though.