Originally available exclusively to those who took up the Engineer VIP Package at Moogfest 2014, Moog's Werkstatt is a build-it-yourself single oscillator synth that was then put on sale in "limited quantities" in the US in June. Now, happily, it's available worldwide.
Officially known as the Werkstatt-Ø1, the synth comes as a no-soldering kit, and assembly is said to be extremely simple. There's no MIDI, but you can control it from a keyboard that has CV out on it.
At $329 the Werkstatt-Ø1 is certainly an affordable Moog, and it's also one that eminently hackable. So, Moog has launched the Werkstatt Workshop - "a creative learning portal containing project ideas, mod tutorials, parts lists, educational lesson plans, 3D printer files, and everything else involved with learning and modifying your Werkstatt".
Check out the Moog YouTube channel to see what's possible once you start getting your hands dirty.