16

That lamp is pretty neat and costs only $16. You can get it here

This nice piece of technology is an alarm clock which projects current time on the ceilings or a wall of your choice. So when you open your eyes at night you always can see your current time.  It costs just $6...

This is probably the nicest computer case you can get under $100. It is fully transparent and it has a water cooling system. With colorful LED lights, running water and transparent walls it can be an eye candy on your desktop.