Default Some accesories oppinion

Here is the list i made, what do you think: (yea i am cheap haha, dont have tons of money)
http://www.ebay.de/itm/NEW-ULTRA-SLI...item3a82517a01
http://www.ebay.de/itm/Black-Desktop...item233f2994e8
http://www.ebay.de/itm/New-Battery-B...item3388724738
Well the last one is just replacement for my back