The Phantasy Star series is set to release a DSiWare installment in the form of Phantasy Star Zero Mini. Japan will receive the game sometime this month, and while there's no assurance that it will see an English-language release, we can certainly hope. One way or another, it will be interesting to see how RPGs translate to the DSiWare service.
It will support four-player wireless co-op and a visual chat feature, and is going to sell for a paltry 200 Nintendo Points.
Sounds interesting to me, and it's great to see other genres representing themselves on DSiWare. Viva variety!