mysticum- I'll let mike13 answer the other questions, but to prevent confusion for you and others reading this, the LM7805 chip I pictured above takes in 7.5V-18+V and gives out a constant 5V. It is a 5 volt regulator as long as the input is over 7.5 Volts. It is this 5 volt regulator that is being utilized in the USB hub in the first post on this thread. I figured a 50 cent regulator is a better deal than a $24 USB hub
