You are wrong there. If you aren't using the USB/Serial to connect to a computer, then there is no problem using the TX/RX pins for serial communication to another device. All that is saying is that the LEDs won't blink under those circumstances.
Thanks for clearing that up.
Pins don't blink for a start
Darn, I was confused all along! And yes, I could try I2C using what you posted, Nick (thanks by the way), or try EasyTransferI2C... Which by the way is a free arduino library made by Bill Porter (www.billporter.info) intended to help transfer multi-variable serial values using TX/RX pins. So same concept...