I have been working on a freelensing technique while walking around sydney city and it is much harder than it looks but I'm really enjoying the results. The technique works by removing the lens from your camera (usually a fixed lens. I've been using a 50) and while on live view you create an effect where only one side of your image is in focus giving the other side a really nice bokeh effect. My advice is to set a your exposure before shutting off your camera and removing the lens.
Its such a great effect that its worth all the effort.