This weekend http://www.datel-japan.co.jp/lineup/japanese/ps3/ps3hub/index.html has launched their new accessory featured on http://game.watch.impress.co.jp/docs/series/ggl/20100730_384252.html dubbed the PS3 Hub for the PlayStation 3, which offers PS3 Slim owners more USB ports alongside a memory card reader.
The add-on accessory connects to the PS3 Slim console providing users with three extra USB slots and several variations of SD card slots.
Below is a picture of the the maximum amount of devices that can be connected with the PS3 Hub to a PlayStation 3 Slim, with some additional pictures available HERE.
Finally, to quote from TheSixthAxis.com (linked above): "For 2,000 Yen, the device plugs into the right-most USB port giving you another 3 extra sockets (so 4 in total) plus plenty of memory-card related goodness, including an SD cart slot that's sadly missing on most models after the launch console.
The ports aren't powered, although you can connect (judging from my translation) an external power supply to give them more juice."
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