I am using a PIC16F876 in conjunction with a CP2101 chip that cost $5.00 from digikey. This chip converts to serial data coming from the PIC to USB serial. I power the PIC from the USB as well. However, not being gifted in electronics, I use a max734 to boost the voltage from 5V to 12V and then take down to a nice steady 5V with a 78L05. The USB 5V power supply flucutates too much and since I am using an AD converter I find it easier to do it this way. The CP2101 is a tiny chip but using solder paste and an oven does the job quite well.