I just bought a 27" iMac last weekend. I am new to the Mac world. Lifelong PC user. I am just looking for some pointers. I love this computer, but the USB ports are a hassle to get to. I am always loading pics to my computer from the USB port and I hate having to move the monitor every time to do it. Couple of questions: How many USB hubs can I run? I am trying to hook up Magic Jack phone and HP printer on one and have another mounted in the front of my desk for downloading pictures and files easily. Is there any certain brand to look for? Does it need to be powered?