I never said Sun or anyone else actually shipped it -- only that it was around, and there was a lot of discussion about using it/trying to create a boot ROM standard one of some type.   IIRC I remember that NCR was messing with it for their 88K boxes (which I had a hand in killing). But NCR switched to all x86-based (their "7 levels "strategy) for everything from Cash Registers/ATMs to their largest Database machines.  They had always been in the "better and cheaper than IBM" business, particularly in their computer products. [1]  So after they switch, their boots start to be all BIOS and EBIOS flavored.

But other Motorola folks I was working with at the time were exploring OF.  I had it on a 68K and another 88K prototype machine at one point (I remember the "ok" prompt), and I remember I somehow had a source distribution tape.  I was an independent consultant then and wrote a couple of drivers under contract for some different folks. I can not think of the firm's name now -- there was another 68K workstation firm here in Lowell, MA.  They actually wrote and made a MacOS emulator work with their UNIX under covers.   I've forgotten most of the details now, but they may have been one of the folks who was playing with OF. 

My memory is that I first encountered it at one of my consulting gigs.

Clem

1] When they threw the x86 everywhere die, they also started using Microchannel (the only large licensee I know of for it -- everyone else stayed with ISA/EISA and then later PCI from DEC/AMD) - tossing out all the Moto IP like VME that so many UNIX systems had used).

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