Sonnet Technologies has released the Allegro FireWire 800 PCIe (PCI
Express) adapter card. This adapter
(http://www.sonnettech.com/product/allegrofirewire800pcie.html)–
which has a suggested retail price of US$99.95 — delivers faster
FireWire 800 performance to Mac Pro, and Power Mac G5, Xserve, and
Windows PCs with PCI Express slots.

It’s backward compatible with FireWire 400 drives and other devices.
According to the folks at Sonnet, the Allegro FireWire 800 PCIe
features the fastest FireWire 800 controller: the Texas Instruments
XIO2213A. To satisfy the high-bandwidth demands of video and pro
audio applications, this latest generation controller enables the
Allegro FireWire 800 PCIe to deliver up to 70 MB/second write speeds.

This card also powers bus-powered external drives and audio
interfaces, so there’ no need to connect an external power brick to
them. This card works in both PCIe 1.1 and 2.0 slots, supports all
FireWire 800 and FireWire 400 peripherals, and features hot-pluggable
and hot-swappable device connection with automatic device
configuration.