A neat piece of computing history - a combination of a hardware dongle and software that lets you run up to System 7 on a NeXT machine (and with some hacking, Mac OS 8).
The latest addition to my NeXT/Mac collection, a Daydream ROM box made in about 1993 by Quix Computerware AG. This unit plugged into the host NeXT's DSP port and contained genuine licensed Macintosh LC ROMs. This allowed the NeXT to boot off the ROMs and thus become a Mac. It was the first time Apple licensed Mac ROMs to a 3rd party and also offered the same performance as a Quadra 950 at a much lower price point and that was including the purchase of the NeXT system. It ran up to system 7.5 officially though with a few hacks 8.1 can be made to run. It is not a Mac virtual machine; it actually boots as a Mac.
This in and of itself is quite cool, but as it turns out, that's not where the story ends. People - including some of the original Daydream developers - have hacked this tool to remove the need for the hardware ROM dongle by inserting the ROM directly into the secondary kernel. This means that if you have a 68k NeXT machine, you can boot directly into System 7 or Mac OS 8. Or, more likely, if you have a NeXT emulator such as Previous, you can boot your NeXT emulated machine directly into System 7 or Mac OS 8 (video).
Incredibly cool, and I had no idea this existed. While NeXT and Apple people were doing these awesome things, I was still using MS-DOS. Strange realisation.