Also interesting is that these boards are claimed to be able to run the first Prescotts from Intel which still have socket 478.
Asus P4P800S motherboard
This motherboard comes in two versions ; the P4P800S and the more expensive P4P800S-E.
These motherboards offer 800/533/400MHz FSB support, Hyper-Threading support, DDR400/333/266 memory support, AGP 8x, two SATA and two ATA100 ports, Eight USB 2.0 ports.
Special is their ASUS proprietary WiFi -b slot. The P4P800S-E has three memory slots and Intel CSA Gigabit LAN supporting 10/100/1000 BASE-T Ethernet, the cheaper P4P800S only two and 10/100 BASE-T Ethernet. The P4P800S-E also offers RAID 0 and RAID 1.
Full specs here.

MSI 848P Neo motherboard:
There are two versions of this motherboard the 848P Neo-S and the 848P Neo-LS. The Neo LS differs from the normal version because it has onboard 10/100 LAN.
It supports 400/533/800MHz FSB (maximum 1.4GHz FSB Overclocked), Hyper-Threading, AGP 8X, DDR266/333/400 (433/450/466/500 DDR also possible when overclocked). It has eight USB 2.0 ports, two Serial ATA ports and two ATA100 IDE ports. Also it has integrated AC'97 sound and optional Realtek 8100C LAN. According to the motherboard picture it only has two memory slots.
Full specs here.

Sounds like some very interesting budget boards because they have all the latest features and technologies. Hopefully they won't be too expensive.