dig around in old PCs for the 5v fan adapter * dual ended cable with 5v fan off of the 5v line *
I cut it half way to the fan and soldered it to where the power in to a 10 port hub goes so it's getting 5v from a HDD connector and I have 4 Erupters all nicely powered and mining ( and 2 of my 3 ants on different USB ports ).
Keep it up and you might be able to do what I did.... buy 2 ants from group buys ( including shipping ) with mined coin!
I also kept hitting some of the BTC/LTC faucets to up my monthly coins and used places like Cryptsy ( an exchange ) or peerbet ( gambling site ) to convert the ' dust ' to slightly larger lumps to go to my wallets ( yes, plural, hard to steal all my coins from 4 different wallet.dat files with at least 2 online! )