BS 2000, the side project of the Beastie Boys' Adam Horovitz, has often been described as "casio hardcore." I'd toss them into casiopunk as well.

casio hardcore bands - bs2000 atom and his package (touring locally soon) reggie and the full effect

Melbourne has quite a Casiotone-using scene; most of it is garage pop (not garage in the house-music sense); bands like Ninetynine, Lacto-Ovo, Minimum Chips, &c., and not all that punk (though one could argue that the punk-rock "here is the E chord, here is the A chord, here is the D chord, now form a band" aesthetic dovetails with garage indie). Perhaps there's a krautrock influence there too.

though, yes, Casiotone is the x0x for indie kids.

Except that krautrock stuff tends to use a real drummer. Just nitpicking.

Do those VL-Tone calculator keyboards count? 'cos I've got one! :)

Ninetynine use a real drummer (for most of their songs; one uses the bleepy drum loop from a VL-Tone-like device), and I think Minimum Chips do as well. Real guitars too.

Though perhaps the next big thing will be Nokiapunk...

NintendoPunk also.

Gerty Farish are casiopunk.

Who are Gerty Farish?

nintendo punk Alec empire released a cd called 'nintendo teenage robots' where the all the sounds are taken from the gameboy.

Someone on Germany created a Gameboy cartridge called the Nanoloop that turned the unit into a noise maker/drum machine/something. It made all sorts of grungy, glitchy noises which could have some use if you like that kind of thing. (I actually have a LM-4 drum kit made of NanoLoop samples.)

Gerty Farish are history now, I think, but they were a duo casio/guitar punk band from Boston. CD on Load Records, sample MP3 at http://loadrecords.com.