BASIC for Saturn

I remember a long time ago seeing a BASIC programming CD for the Saturn where you could play around with BASIC and make 3D games. Anyone remember the name of it or *cough* know where I might find it?
I have seen that for sale on ebay before, I always thought it looked interesting, but I never bought it. Sort of wish I had now, its become very rare :(
I have researched a lot on this one. I have found some cool games made in it. But i think it is only japanese, so it would be hard to get one. I would really like to have one if i could get it.