USB Hubs?

I was looking these over. All I want is to avoid having to move to the back of the tower to reach the port, and the ability to have a few items plugged in since I have a printer that occupies one of the two ports on the tower all of the time.

My question concerns quality and price. There seems to be a range of about $4 to as much as $60 for a four-port unit. What features make the difference? I've got the standard household stuff, I-pod, camera, etc. , but I don't use it all at the same moment. How much do I need to spend to get the job done? Thanks.