I know a lot of people have tried booting the E-manchines EZ200 from other devices beside a USB floppy or Zip and haven't had any success. I have been able to take a Sotec 32Mb USB flash drive and boot from it.
I received the Sotec for free as part of buying their laptop. It came w/o a cdrom with drivers. It works with Mac OSX & OS9 and WinXP, but without drivers won't work under Win98. Neither of these OS'es allowed me to do anything more then format it. MacOSX would allow me to partition it but offers no way to set a Fat partition as bootable. I found that this past week, that my freeBSD 5.0 system recognized the USB Flash Drive and I was able to fdisk it and mark it bootable and write a standard MBR. Unfortunately, BSD's fdisk left the partition as "hidden". I could see the flash drive via Disk Utility (MacOSX) and viaSystem (WinXP) but the partition would not mount. Luckily MacOS9 ignored the "hidden" property and I copied a Win98 reseque disk to it. This also seemed to unhide the partition and it subsequently would mount under MacOSX and WinXP.
I then tested it on the EZ200 and it boots! The drive, like a USB Zip appears as drive A:
I've searched the web for drivers for Win98 for this device and found several other brands that do come with utilities to format the drive as a bootable drive. One brand even offers to make the their flash drive appear as a USB floppy or as a USB Zip.
The advantage of booting from USB flash drive is considerable. You can get them in capacities as high as 512MB . The file system can be prepped/updated on a more powerful system and then used on the EZ200. Some models come with a write protect switch, thus allowing the EZ200 to be a very secure system.