For a small group, if you are interested in how the University of Washington’s BLA program works check out my blog at http://designcoffeearchitecturelife.blogspot.com/. I am trying to post almost daily now 😀
try amazon or newegg.com any external hard drive that has a usb plugged into it should be fine. For more portable something like this http://www.newegg.com/Product/Product.aspx?Item=N82E16822101224 or for something more stationary but more room you could go for one of these http://www.newegg.com/Product/Product.aspx?Item=N82E16822145466 . biggest difference between the two is that the larger one is going to need to be plugged into an outlet to operate while the smaller can be powered by the usb port on your computer. either one should be ok for your mac but once you are using if for the mac I have heard of issues of the formatting not being able to go back to PC completely an vice versa. Good luck!
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