I posted some time ago about upgrading a mobo without Windows or DOS. That process still needed one to use a floppy to perform the update. On more modern systems we can get by with nothing but the hard drive you already have installed. I recently picked up a Dell Optiplex GX280 from the usual source and of course it came without the hard drive and RAM, and it never had a floppy drive installed. I sourced a hard drive from my previous workstation, picked up some new RAM and booted the Ubuntu 8.10 install on the drive. The machine was still running the original A00 BIOS it shipped with. I then did a bit of digging and found out that Dell has been working to make updating the flash BIOS on their systems much easier under Linux -- so easy that it's literally just about cut-n-paste for the command line wary. A blog post gave the steps to get it done under Debian, and they worked just fine under Ubuntu. I already had the larger uni and multi repos enabled so all it took was to nab the correct .hdr BIOS image and get to work. It wouldn't take much work at all to get this into a point-and-click setup and have it be as dead simple to do as under Windows.
I'm surprised how easy this was to do, and this system is four years old. Linux is really coming into it's own.