Hmmm. I think that's going to mean I can only fit 2 into the hub
Thanks for checking the measurements for me so quickly!
Looks like I may need to look at getting one of these Anker USB hubs
http://www.ianker.com/product/68UPHUB-B10U
They look like the most popular choice for running multiple USB Block Erupters. Unfortunately, it looks like they only sell them through the US Amazon store and don't ship them internationally. Time to see if the MyUS service I signed up for works as advertised!
What fan are you using for cooling? I saw an Arctic Breeze 92mm USB one that looks like it should do the job, it was listed on Amazon's "Frequently Bought Together" list when I was looking at the Anker USB hub.