Just picked up a PNY eSATA expresscard for use with Time Machine/WD myBook. $15 for the expresscard, another 10 for the eSata 6' cable and on my way. Got home, plugged it in, Leopard recognized it as a mass storage controller, but that was it. Downloaded the drivers for Griffen Technologies eSATA expresscard, and it works great! Every eSATA expresscard adapter I've seen looks identical and seem to all use the 3132 controller, which is why I figured it was worth a try. Anyway, it's worth it. I copied a 5gb disk image to the myBook in 1m02s, MUCH faster than USB2.0, and it doesn't load up the CPU like usb does.