I modified a Rosewill 7 port hub from Newegg. It came with a 2A adapter which would've only been enough for 3 erupters or so, but I removed the host diode and shorted the DC input diodes. It had four 1A schottky diodes, one on the host side and three on the DC jack. They will be easily overloaded and will burn out or cause problems past 3A of current.
Great picture! Leaves little doubt that the three plugs on the right are one hop away from the input but the four on the left are two hops. Very important if you are going to cascade hubs.
One minor nit. The diodes also protect against hooking up the power backwards. It wouldn't be hard to pigyback a couple of extra 1 amp diodes to increase capacity if one wanted to increase capacity without removing that protection.