Make 791
This fellow is building an Arp 2600ish modular using Music From Outer Space modules, wow! He writes –

So, 17 years ago I made a huge, HUGE mistake… I sold my dearly beloved ARP 2600 in order to buy an Atari STFM (remember those?)

I always regretted doing this, and recently thought about getting another 2600. The problem is that second hand prices are ridiculously high – one went on ebay recently for over £2,500! and the Macbeth M5 at £3,000 is way beyond my reach.

What to do, what to do??… Build my own!

The BroadWave synthesizer. Thanks Kaden! – Link.