Seagate this morning kicked off it yearly overhaul of its FreeAgent external drives with both a new look and some rare features. The FreeAgent Go (pictured) and Go for Mac are both claimed as the thinnest notebook-sized drives at 12.5mm (just under 0.5in) but also have an optional dock that cradles the drive at home, simplifying the process of porting the drive outside of the home. The Mac edition also switches from USB to a rare FireWire 400/800 interface and is pre-formatted for the HFS+ file system out of the box.

Both the regular Go and the Mac edition are available in silver, while the universal drive is available in three extra colors. The basic drive is available this month at $120 for a 250GB drive, $150 for 320GB and $240 for a 500GB version. The extra cost of the faster interface on the Mac drive boosts the cost to $160 for a 250GB drive and $190 for a 320GB disk, while no 500GB version is available.

Larger Desk Drives also join the update and exploit Seagate's in-house development of a 1.5TB disk to improve the capacity of its external disks: both the USB-based universal version and the FireWire 400/800 Mac model have the option at $280 and $350 respectively. Seagate's lineup now also starts at higher capacities and ships in 500GB, 640GB and 1TB versions for $130, $150 and $230 for the USB models. The Mac lineup is simpler at $170 for a 500GB model and $270 for a 1TB edition. Most drives should be available this month while the 1.5TB disks ship in October.

One top-end series, the XTreme Drive, includes separate external SATA, FireWire 400 and USB connections to provide the user's pick of interface. It ships in 500GB ($150), 640GB ($180), 1TB ($260) and 1.5TB ($300) models and sees similar ship dates as with the usual Desk Drives.