There's a book called "The Incredible Sound Machine" .

It's on Amazon -- I'd give ya the direct link but the computer in the candystore I'm in right now doesn't copy/paste lol

Sorry sorry.

In the book Chapter 9 is is about boxmacMIDI & has an absolute ton of sequencers listed.

For example, the company name "Mark Of The UniCorn" springs to mind.

:b&w: