Hrm.. ok, this is interesting. Could you give me a couple examples that I could start experimenting with ? I have some resistors, I could make a resistor potential divider, What values would be appropriate? Looking over the wikipedia page Voltage divider - Wikipedia
It looks like their example of 6v from 9v, is the same ratio 3.3v from 5 v. In which they say R1 should be twice the value of R2. I've looked, and not found a pair of resistors that are suitable, however I have some tiny resistor packs, and I could bridge 2 resistors to make one resistor thats half the value of the other resistors. They are pretty low resistance (63 ohms).
How about the ics or transistors? I have some routers that I can pull parts from, maybe I have the transistors already?