You can already buy an infrared camera, but only if you have hundreds of dollars to sink into the purchase. An inexpensive infrared-modified camera, originally developed by Public Lab to monitor damage to wetlands after the BP oil spill, is now available through Kickstarter.
The Infragram project has already handily topped its $30,000 goal and gives you several different options for obtaining a cheap infrared camera. You can do it yourself and modify your own camera for $10, buy a pre-modified bare-bones Webcam for $35, or buy a ready-to-use point-and-shoot camera for $95.
All of this is made possible thanks to a "superblue" filter. This filters out red light and allows the camera to read infrared instead. The $10 pledge comes with a piece of filter, a white balance card, and instructions for installing it in your own camera. Keep in mind, this is probably going to have to be a permanent modification, so you might want to try it on a cheap camera. If cracking open a camera isn't your thing, then the Webcam or point-and-shoot options are a better choice.
There are a few steps to getting the infrared image. You upload your images to a Web site that will process the images, creating the familiar infrared look that we're used to seeing. That piece of the puzzle is still under development, but it is expected to include image analysis tools that will help you make sense of your photos.
Infragram is ideal for monitoring plant health, whether it's your home garden or a larger environmental effort. The more plants are busy photosynthesizing, the more near-infrared light they reflect. This affordable camera should open up a window into that fascinating world for a lot of people.