From Ken Shirriff - the man who brought us the incredibly useful Arduino IR library comes another excellent project idea. Using a PC running the Python web server, a web page with graphical remote control is available on his home network. Clicking on the web page accessible by any web-enabled device (such as the phone below) sends a code to the web server, which sends it over the serial port to the Arduino, which sends it to the IR LED, which controls the hifi (or other IR-controlled device).
This is another successful Arduino integration of two technologies to make life easier. Using this method on a wifi-enabled web device allows control of any IR devices anywhere within wifi range, offering a much larger radius of control. What a great idea! For more information and to get started, visit Ken's site here. To get started with your own Arduino-embedded projects, consider using the Freetronics LeoStick - one of the smallest Arduino-compatibles on the market with onboard USB, RGB LED and piezo: