USB drive boot manager

Hi /prog/

I have windows installed to one HDD, and *nix to another. ATM i use the BIOS to switch between drives at boot. This is because I want each drive to remain bootable on its own [eg if i brick one of the two OSes]. Obviously this isn't very efficient.

I'd like to have a boot manager installed on a USB drive to select between which to boot, but I want to avoid doing anything that modifies the drives so that they become unbootable without the USB stick either.

Can you point me in the direction of some software that can do this? I've looked at Plop, YUMI, GRUB and LILO but i'm not really sure which best suits my needs, and if its possible to use them in the way i describe [from USB stick, with USB keyboard and without modifying their MBR etc].

>>28
Interesting code, I don't think you can push/pop into segment registers and you may not be saving the driver Id but maybe I'm wrong

>>29
Your assembler should be as, the syntax is Intel (with a lot of spelling mistakes), after compiling it I guess you'd need to inflate it to fit a 512 byte sized boot sector with ld instructions such as
OUTPUT_FORMAT("binary")
OUTPUT_ARCH(i386:x86-64)
SECTIONS
{
   .start16 0x0000 : AT(0x10000) {
      start16.o (.text)
      start16.o (.rodata)
      start16.o (.data)
      . = NEXT(16);
   }
   .text   0x10000+SIZEOF(.start16) : AT(0x10000+SIZEOF(.start16)) { *(.text) }
   .rodata ALIGN(16) : { *(.rodata) }
   .data   ALIGN(16) : { *(.data) }
   .bss    ALIGN(16) : {
      __bss_start = .;
      *(.bss)
      *(COMMON)
      . = ALIGN(16);
      __bss_end = .;
   }
   __bss_quads = SIZEOF(.bss)>>3;
}
and finally to commit a lonely sector do the usb stick I can't help you with, ouch