How to flash motherboard BIOS from Linux (no DOS/Windows, no floppy drive)

You've finally made the move to a Windows-free computer, you're enjoying your brand new Linux OS, no trojans/viruses, no slowdown, everything's perfect. Suddenly, you need to update the BIOS on your motherboard to support some new piece of hardware, but typically the motherboard vendor is offering only DOS based BIOS flash utilities. You panic! Fortunately, this problem is easy to solve...

How to flash motherboard BIOS from Linux (no DOS/Windows, no floppy drive).