Program Arduino Pro Mini with USB-to-Serial adapter

This is a good video tutorial for programming (or flash) Arduino Pro Mini with USB-to-Serial adapter. Using 3 different USB to Serial modules to program a clone Arduino Pro Mini. The chips are the FTDI FT232RL, the Silicon Labs CP2102 and the Prolific Technologies PL2032HX.

HC-05 Serial Port Bluetooth Module (Master/Slave)

HC-05 module is an easy to use Bluetooth SPP (Serial Port Protocol) module, designed for transparent wireless serial connection setup.

Serial port Bluetooth module is fully qualified Bluetooth V2.0+EDR (Enhanced Data Rate) 3Mbps Modulation with complete 2.4GHz radio transceiver and baseband. It uses CSR Bluecore 04-External single chip Bluetooth system with CMOS technology and with AFH(Adaptive Frequency Hopping Feature). It has the footprint as small as 12.7mmx27mm. Hope it will simplify your overall design/development cycle.

source: http://wiki.iteadstudio.com/Serial_Port_Bluetooth_Module_(Master/Slave)_:_HC-05

Arduino ISP

The Arduino ISP (http://arduino.cc/en/Main/ArduinoISP) is a tiny AVR-ISP (in-system programmer) based on David Mellis' project FabISP (http://fab.cba.mit.edu/content/projects/fabisp/). With this programmer you can upload sketches and burn the bootloader on any AVR based boards, including Arduinos. By uploading a sketch with an external programmer you can remove the bootloader and use the extra space for your sketch. The Arduino ISP can also be used to burn the Arduino bootloader, so you can recover your chip if you accidentally corrupt the bootloader. Burning the bootloader is also necessary when you use a new ATmega microcontroller in your Arduino, and you wish to use the bootloader to upload a sketch via the USB-Serial connection.

For more details about using the Arduino ISP please visit the Getting Started page.