eSATA Is Ditching The Power Cable
For early adopters of eSATA, a fairly new type of connectors for external hard drives, there is an extra hassle of connecting the additional power cord.
A new standard called Power Over eSATA is set to clear this hassle, as it is becoming the standard eSATA connection for delivering power over the core cable without the need for an external source. I can only foresee that its next competitor would be the new USB 3.0 standard.
via CNET Crave