According to pictures below (courtesy of Gemaga, linked above) this eSATA adapter dubbed the PS3 HD Plus PHE-01 latches to the bottom of any PS3 promising connectivity to an external SATA hard disk for some majorly powerful storage capacity.
Sure, there are other ways (such as THIS or THIS) of getting massive amounts of bytes onto the PS3.
One can simply swap in a new internal 2.5" SATA into the system, or even just hook up any old USB hard drive with little hassle; however, the latter won't give the same transfer speed as an eSATA.
From the looks of it, the PHE-01 also comes with an additional four USB ports.
Unfortunately, aside from what can be derived from the pictures there aren't any further details on this product yet... time will tell.
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