Newegg offers the ASRock Mini ITX Quad APU Motherboard, model no. QC5000-ITX, for $69.99. This $20 mail-in rebate cuts it to $49.99. With $6.98 for shipping, that's the lowest total price we could find by $22. It features an AMD FT3 Kabini A4-5000 1.5GHz quad-core APU, and supports up to 32GB RAM, with a PCI-Express 2.0 x16 slot, mini PCIe slot, four Serial ATA 6Gb/s connectors, and six USB 3.0 ports. Rebate ends July 31.
Update: Specs corrected