How to make a lab magnetic stirrer with a motor from a CD-DVD drive unit, a hard disk drive magnet and some esay materials like wood, a switch, jack connector, etc.
You only need to buy the magnetic stirrer bar, (or stir bar) i.e. on Ebay. It is not recommended to DIY the magnetic bar because the pro ones are cheap and covered with teflon, so they dont react with chemicals. http://goo.gl/dbXbIv or http://goo.gl/v7mYBL

http://en.wikipedia.org/wiki/Magnetic_stirrer http://en.wikipedia.org/wiki/Stirring_rod