I've got the orgasm-inducing Beatmania IIDX controller from Konami, as well as their European Beatmania controller. That one has a great turntable, but the buttons leave a little to be desired. And I have the Topway drum controller, which works surprisingly well, considering that it's a Topway. I had a Topway guitar controller, which was heavily modified and worked extremely well, but it died.

Oh, and I've got a couple pirate Famicom clones with built in multi-cart ROM. Heh.

Shopping list:
Pop'n Music controller
Rez Trance Vibrator (what the hell)
Maracas