Quite often with the Coreboot ports mentioned on Phoronix, the consumer motherboard targets often end up being hardware that's rather old or for motherboards/laptops that aren't widely available. Today a new motherboard port landed in mainline Coreboot and it's for a board using Intel's B75 Express chipset for handling Sandy Bridge and Ivy Bridge processors.
The new port is for the Gigabyte GA-B75M-D3H, a micro-ATX motherboard that's fairly decent if you're still using SNB/IVB era hardware. The Gigabyte B75M-D3H is small but packs in four DDR3 ports, dual PCI Express 3.0 x16 ports, VGA/DVI-D/HDMI connectivity if using Intel HD Graphics, Gigabit Ethernet, etc. Of benefit to those experimenting with Coreboot, this motherboard features dual UEFI protection for storing two BIOS images to switch between in case of failure. The motherboard is reviewed well on various Internet retailer web-sites and is selling for $70~80 USD.
The Gigabyte motherboard port was done by Damien Zammit and is based on Coreboot's Lenovo X230 port. Damien says Coreboot on this board can boot to Linux via SATA or USB and all USB ports are reported to work. However, sometimes the native RAM initialization fails and the VGA graphics do not currently work. More details via this Git commit.
Those interested in this new Coreboot-friendly motherboard can find it at Amazon.com.