Melzi with Bluetooth. The no-soldering way.

Instead of connecting the BT module to the serial port 0 with super fine soldering and a great possibility to fry that board like described here:
[reprap.org]

I did connect the BT module to serial port 1 on the EXT connector (5V, Gnd, Rx1, Tx1) and i did change the firmware to listen on this port.
Changes are in MarlinSerial.h und MarlinSerial.cpp. Attached patch is for nophead fork. Do a "#define SERIALPORT 1" in config.h to swap to serial port 1.

[imgur.com]

Wow! I only found this by accident! This is a great idea!!!
Too bad I found it after soldering the pins
Should be on the wiki, too...