Take a piece of developed film. (that old kind we used to have before digital cameras)
Cut a piece and place it over the lens of your digital camera.
Aim at some vegetation and take a picture.
Wonder why the grass turns blueish.
What we're actualy doing here is filtering out the normal light, letting mostly Infrared light into the camera.
You can easily test this by aiming a IR remote control at the camera, you can't see the lamp blink , but the camera can.
You'll need long exposure times, so preferably use a tripod or something steady.
These pictures was taken freehand with a mediocre camera, but i'm sure you could achieve amazing results with a better camera and a tripod.
Have Fun =)