2-Port NitroAV FireWire800/1394b Professional Express Card

2-Port NitroAV FireWire800/1394b Professional Express Card (34mm) Interface Adapter (MacBookPro)

http://www.nitroav.com/product/444/

Quote from manual:

"Note: The Express Cards do NOT supply the power over
the bus to the FireWire cables. All devices attached to the
Express Card need to utilize there own power supplies, or you
need an AC adapter to provide the power through the Mini
DC-Jack on the Express Card (at the side of the Express Card).
However, not all 1394 devices need the bus power. The DV
camcorder does not use the bus power, for example."