OCZ and MSI have both started talking about OCZ's Throttle eSATA drive and MSI's eSATA and USB combo, called the Power eSATA. The good thing about this port is that eSATA devices no longer need extra power via an adapter or USB cable, which makes the Throttle even more functional.
In addition to the fact that it does not need an extra USB cable, the Power eSATA port should be up to 8x faster than normal USB ports, and MSI is the first manufacturer to include Power eSATA on an AM3 motherboard, the MSI 780FX-GD70. In addition to the 790FX AM3 motherboard, MSI has included the Power eSATA connector on a wide range of its notebooks as well.
OCZ's Throttle on the other hand is available in 8, 16 and 32GB capacities and offer read and write transfer rates of up to 90MB/s and 30MB/s, of course when plugged into an eSATA port.
You can find more info and full list of MSI's Power eSATA equipped notebooks
here, and you can check out the prices of OCZ's Throttle drive
here.