Freelensing is a technique where you remove the lens from the front of your SLR or interchangeable lens camera, and hold it in position rather than locking it in place in the lens mount.
Tilting the lens back and forth gives you an effect that looks somewhat similar to that of a tilt-shift lens or a selective focus lens like a Lensbaby. Expect light leaks and lots of bokeh thanks to the shift in the plane of focus.
A word of warning, freelensing is not for the faint-hearted, as you could drop your lens or get dust and dirt on your sensor. The results are worth it, but proceed with caution.
A subtle example of freelensing at work. Watch the video for more examples.
(Credit: Lexy Savvides/CBSi)