SeaBIOS
SeaBIOS is an open source implementation of a 16bit X86 BIOS. SeaBIOS can run in an emulator or it can run natively on X86 hardware with the use of coreboot.
SeaBIOS is the default BIOS for qemu and kvm.
The coreboot SeaBIOS page has information on using SeaBIOS in coreboot.
Please join the mailing list to contribute to SeaBIOS.