Answer: You can't!! (Well I'm assuming that file is already compressed) What you can try doing is using a filesplitter program to split the file into chunks (and generate a small .bat file to join them back together!), that will fit on to floppies. Once you have all the chunks together on a harddrive, run the .bat file to join all the chunks back together into the full file again.

If you have trouble finding a DOS filesplitter, I think I have a simple one somewhere, in the dark and seldom visited corners of my HDD!

Floppy disks can hold more than the advertised 1.4 MB, but not if they're formatted with FAT12 by DOS.
You'll need a programme that can write the raw disk image to disk directly, bypassing the filesystem. I know these exist for DOS but you'll need to google around for it. In Linux, one can do something like dd if=diskimag of=/dev/floppy (assuming /dev/floppy is a symlink to the floppy device) to write directly to the floppy.

That's not going to be much help: the file in question is a diskimage for a bootfloppy.

Not at all. You can do it just fine from Linux. What you need is a computer with a working operating system to create the floppy with.

For some reason, I remember having to format a floppy to be 1.66 mb or something like that, and after that it fit just fine.

I'll try and find the instructions.

Thanks for all the help!

1.44 MB floppies cannot hold more than 2 MBs.