Sanwa USB-HUB256BK works quite well, both with Windows and Raspberry Pi:
http://www.amazon.co.jp/SANWA-SUPPLY-USB-HUB256BK-%E7%A3%81%E7%9F%B3%E4%BB%98%E3%81%8D10%E3%83%9D%E3%83%BC%E3%83%88USB2-0%E3%83%8F%E3%83%96-%E3%83%96%E3%83%A9%E3%83%83%E3%82%AF/dp/B003BGY2YA

Self-powered, 5200 mA.
I use it my rig: https://bitcointalk.org/index.php?topic=288621.0