there is a way that I found. here's how i did it, approximately.
1) you must write a master boot record to the first sector of your flash drive. this is the only way i could get mine to boot. This could be specific to my motherboard, however.
1.5) fdisk your flash drive and make a partition of type fat16.
1.6) run mkdosfs on the partition you just created.
now... i don't remember exactly how the next steps go. but:
2) you must use the syslinux utility to make your flashdrive bootable.
3) you must mount your .iso as a loopback device, like so :
# mount -t iso9660 -o loop file.iso /mnt/iso
4) go into the /mnt/iso direcory (or wherever you mounted your iso) and copy everything to your flashdrive. now let me think ...
5) go into the directory with the boot files in it. copy them to the root of your flash drive.
6) rename isolinux.cfg --> syslinux.cfg
and that should work. i'll be right back with a better link if you need more info.
here's a link for in case you're in windows.
here's for in case you're in *nix.