The effect is a bit like a "crash zoom", something I used to risk on my old manual SLR but wouldn't try on my newer auto-focus lenses.
The Lensbaby has a locking mechanism that allows the user to lock the Lensbaby in place and then fine tune the focus by rotating the center barrel focusing knob. The tilt can also be changed by rotating the knobs on the end of the focusing poles.
Here's a Flickr set of photos tagged as "lensbaby".. http://www.flickr.com/photos/tags/lensbaby/
Though I've not really found an amazing example to make me want to get one of these things
