To answer mr.Gulli regarding his remark on 27/7/03 6:23PM
The reason why MacOS and windows moved to PMT. Is quite simple. It's based on two things.
One is said in the article on top of the thread. CMT let's control from within the application while PMT let's control from whitin the OS (this is oversimplified, I know, but for a non-programmer this is understandable). So therefore PMT will undoubtly make the OS more complex.
Also remember when the 1st Archimedes arrived. It had no proper OS and Acorn Ltd. had to speed things up. Obviously adding PMT would probably added considerable development time before launch of RISC OS 2 (which was the first full version of RISC OS AFIAK). I'm sure that many ppl where eagerly awaiting ROS 2 and really wanted to ditch Arthur. So I'm convinced that this is the prime reason why Acorn opted for CMT instead of PMT.
As for MAcOS X. DO NOT forget that Mac OS X is basicly a BSD-style Unix kernel with a MacOS UI on top of it. Unix is much older than RISC OS and is developped (or better suited) to mission critical environments while RISC OS is just a "consumer" OS.
As for Windows. Proper (decent) PMT didn't arrive until Windows NT. Basicly FAT-based windows environments use a DOS-based filing system with GUI bolted on. Even a MAC OS classic is better than that albeit also CMT (more or less).
I think that if you'd like something similar with a RISC OS feel then you better look at linux with the ROX-filer. This is an attempt at having a RISCOS-like UI on top of (a PMT) Linux. Though I'm not sure whether anyone has compiled ROX to a Linux variant on the RPC or other ARM machines. Maybe that is an interesting idea.....
ARM Linux, ROX and some emulator for "classic" apps. We might even call that combination "RISC OS X"