This article is for those who loved music that was coming out from the Amiga/ Commodore 64/ NES or any other old console.
Chiptunes are found in most cracktros/intros/demoscenes or games. They consist of basic waveforms such as: sine waves, square waves and sawtooth or triangle waves, and basic percussion. According to wikipedia: The "golden age" of chiptunes was the mid 1980s to early 1990s, when such sound chips were the most common method for creating music on computers.
Crackers would release a cracked version of a software/game accompanied by a small executable through which they could demonstrate their programming skills. Such executables are called cracktros (crack-intro) and they use visual effects and chiptunes. The first cracktro I enjoyed listening was one from the group named CLASS and the soundtrack is composed by Maktone. Cracktros released by him can be found on his official website (see below).
Chiptune friendly links:
http://www.last.fm/tag/8bit - listen to some tracks online and download them if you like
http://www.last.fm/music/Maktone - read about Maktone (my hero and the first composer I've ever head a chiptune)
http://www.maktone.tk/ - Maktone's official website with cracktros and music in different formats
http://www.chiptune.com/ - retro site with a very cool old computer interface and tons of chiptunes
http://chiptunes.free.fr/ - not too stylish but usefull
...and last bot not least: http://en.wikipedia.org/wiki/Chiptune from where you can document yourself