I have done this - selling it now.
I did a post to Craigslist on this just this week - since I have sunk my teeth into few other flash outfits this one is redundant.
the ad text: So you follow the strobist blogsite, are all keen about getting better taking flash shots with inexpensive multiple flash heads, and all, but the cost of buying a lot of AA batteries is really starting to bite. Or you have NiMH units, but they are dead when you want to use them. Or you don't mind the cost, but when one flash unit starts to recycle slow, and you don't notice right off it did not fire, or only fired at part power right away, the retake requests you need to make drive you nuts.
This is your ticket. An old PC power supply - It puts out 5V at up to 22A. The 4-AA battery flash units you have will have never recycled faster, even from full manual dumps, and all of the flash units recycle at the same rate all day long. No need to modify most battery compartments- just don't slide the battery cover fully closed. The screws in these wood blocks that are the contacts are set up for Vivitars, but modifiaction is easy to sout other configurations. Connectors and wire are from Canadian Tire to hook up more flash units. This set comes with 2 falsh blocks, and three connectors on the power supply.