Thanks again twister.
Regarding the external HDD does it still require an external source to be powered even when plugged into a powered USB hub?
As for MHL and USB OTG, the Note 2 and S3 (I believe) are capable of it. But to get it working, you'll need something like the Samsung Smart Dock Multimedia Hub. Or some hub that allows USB + MHL + power connection. It's known that the S3 and Note 2 cannot power the MHL adapter on its own. Even with that, I'm not sure if you can plug another hub into it and still work with it. Though it'll be interesting to see.