Amazon.com: SABRENT 4-Port USB 3.0 Hub for iMac Slim Uni-Body (HB-IMCU) : Everything Else
27” Mid 2010 iMac Disassembled
SABRENT Premium 4 Port Aluminum USB 3.0 Hub (30" Cable) for iMac, MacBook, MacBook Pro, MacBook Air, Mac Mini, or Any PC [Silver] (HB-MAC3) : Everything Else
Apple iMac refresh rumors resurface: USB 3.0, CPU updates and possible touchscreen? - SlashGear
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BYEASY Powered USB 3.0 Hub,7-Port USB 3.1 Splitters BC 1.2 Charging for iMac,PC 726587004025 | eBay
Adding USB3.0 to late 2009 iMac (11,1) | MacRumors Forums
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Mobee Gives Your iMac Four 2 Amp USB 3.0 Ports with Magic Hub
Sticking with USB 3.0, Hewlett-Packard torpedoes "fancy" Thunderbolt - 9to5Mac