Continuing the discussion from VHS SMD March Build Night - FTDI USB Serial Breakout Mar 4 2016 ~$CA10:
Not much interest in the USB serial board so I added an 8 channel 3.3v/5v bidirectional level converter board to the options. These are super useful for interface Raspberry pi to 5V logic and Arduinos to 3.3V logic.
Board details at 8-channel Bi-directional Logic Level Converter [TXB0108] : ID 395 : $7.95 : Adafruit Industries, Unique & fun DIY electronics and kits