MegaMacs offers the used Apple MacBook Core Duo 2.16GHz 13.3" Widescreen Laptop in White, model no. MB061LL/A, for $399.99 plus around $18 for shipping. That's the lowest total price we could find for a used unit sold elsewhere by $154, although we saw a comparable refurb (with a larger HDD) for $4 less last week (since expired). It features an Intel Core Duo 2.16GHz dual-core processor, 13.3" 1280x800 widescreen LCD, 1GB RAM, 80GB hard drive, DVD/CD-RW combo drive, iSight webcam, Airport, Bluetooth, and more. Deal ends December 22 at 3 pm ET.

A 30-day MegaMacs warranty applies. Note that this unit comes with an OS, but it's unclear which one is installed. It may have scratches on its case.