+2 on SJ and SDMB's lists.
I would get the keyboard version of the Moog though, for tweaking live.
Plus
Prophet 800
Komplete 5 and Kore 2 (this one actually falls into the just start making music now category TD is talking about)
Novation Remote 61 SL
A classic analog synth- an Arp 2600 or some other old semi modular. Either that or start in on a modular system from one of the manufactures doing it now.
The other one that people seem to be forgetting is a Lemur, learning curve there, but worth it from what people say.