It seams none knows...
There is on the net PLoP Boot Manager
http://www.plop.at/en/bootmngrusblog.html but you must be damn lucky to boot from USB. I'm not, so this didn't helped me. I writed an e-mail to the person that is writing PLoP Boot Manager and we had an discussion but there are some chances that he will not be able to make PLoP Boot Manager boot from USB with my motherboard.
I read the forum. Well I can't find in online shops from Romania Transcend Solid State, IDE CF card reader or something similar so this solution is useless for me. (You can say buy it from another country but will you pay the transport? (The transport is at least 2x price of the damn thing)). It's more easy to find an USB stick. m0n0wall don't need a damn good CPU so old PC are usually used, and a lot of the old PC can't boot from USB. Why not use a CD? Good question but I have another question. How you upgrade m0n0wall runing from the CD? You have to write another CD or to use a CD-RW also the settings are not store on the CD... Also there is no guide on how to install m0n0wall and another OS on the same hard drive, it will be a bit strange to buy a 80GB HDD (smallest HDD I can find on maket) just to write m0n0wall on it. Why do I need another OS on the PC where I use m0n0wall? Sometimes the ISP have problems (my connection is a PPPoE one) and they ask me the error I receive when I try to connect. Let's just say it's a 678 error in Windows, in m0n0wall it just say PPPoE connection timeout (I know the 678 error and the PPPoE connection timeout are both useless cause there can be a lot of problems that generate this error like: their server is down, cable problems on the road from them to me, something that is not powered on the road from them to me, some of their hardware is malfunctioning... but the person that is answering when I report the problem just want a damn error number.). So I will have a damn long discusion when I will call my ISP to report a net problem cause they ask me for the number of the error, and ups m0n0wall don't gave me one. It's not my fault that my ISP hired some idiot people that thing Windows is the only OS...