Build things like combat arenas to unleash things upon each other; include mechanisms for blasting them around with water, or melting everything to ash with magma, or dropping them. Include a method to reliably and titan-proof-ingly trap anything you put in, in case FPS dies or you want to reuse them. Include magma-proof traps. And heck, dragonfire-safe too.
Build a tower for the express purpose of hurling enemies off the top. Bonus points if it's a minecart-automated system. Double bonus points if it is easy to retrieve equipment from the fallen creatures, as well. Dwarfbonus if mandating nobles can be persuaded to take a look from the upper floor. Super-Dwarf-Bonus if there's a method to create a fireball on top of the tower. Armok Bonus for towers that can also be used to rain other things down on invaders. Mega Armok Bonus if you level the world down to the magma sea, so that only your tower of stone still stands, and one lonely bridge to the edge of the map. Bonus points on THAT if the bridge is trapped six ways from HFS. More points for seven.
And double it ALL for the doomsday lever dropping your tower as a spear into HFS. *Should probably find a way to reliably conquer underground reaches before attempting to construct this mechanism.
Extra Bonus Points: Do it during a siege, and take the siege with you.
And a few more points if the tower is black as the night, and winged creatures upon which black figures ride circle the top.
See, there's all KINDS of idiotic stuff you can do for the heck of it.
Warning: Above may cause dwarf deaths, mutilations, crippling, damage, injury, suffering, unhappiness, tantrums, sickness, wounds, bad luck, bad days, displeasure, sadness, terror, horror, torture, ... (list continues) ... and may also cause severe Dwarfiness, resulting in paralysis of the body due to disuse in front of a computer.
But at least it glows while you watch it!