Jechavarria has designed this breakout board with the MCP23017 I2C IO expander:
With this board you can drive a 2×16 display LCD with only two signals (I2C).
I also develop some code (in C) to manage this device, based on a AT89C51RE2 microcontroller. Please feel free to visit www.jechavarria.com for more info, schemes, and source code!
Via the forum.