I'm pretty sure it's a euphorbia of some sort but I could't tell you which one exactly. Maybe a caput-medusae...maybe.
I used to grow a lot of cacti/succulents (before the orchids displaced them all) and I always found euphorbias to be very easy growers. Considering most (if not all?) are native to S Africa...it should be a breeze for you to grow.
I grew them well but I never could get flowers...you should have better luck in that department.