I used an LCD shield to display the current temperature and speed of the fan, but you can use the circuit without the LCD display. You also need to select the transistor by the type of fan that you ...

This Instructables guide will show you how you can use an Arduino to control your TV, DVD player, VCR, and countless other home electronics.

20x4 LCD display, and possibly a serial adapter for this to minimize the pins required from the arduino RGB LED connected to the arduino Optical/ultrasonic sensor connected to the arduino Computer fan ...

This is an easy tutorial showing how you can control the brightness of an LED or adjust the speed of a DC fan using Arduino Board, a small BC547 transistor and a potentiometer.