Korg Volcas. Arturia also has some fairly affordable analog synths like the Microbrute. It doesn't have any presets, so you have to figure out how to create sounds on your own and the manual that comes with it is great in explaining oscillators, filters, etc.
Had the Microbrute, volca beats/keys/bass. All of them sounded awesome. The only problem is you couldn't really make songs (with distinct parts) without an additional controller (a squarp pyramid would have been cool. ) and the whole point was to not have to use a computer.
If I did it again a I'd probably go with an octatrack or mpc live or something where I could do more in a single box.
