Here is a great free-lensing tip courtesy of DIYP reader Timothy Blair. In a nutshell, free-lensing is creating a tilt/shift lens by separating a lens from the camera body and holding it by hand. You can read a few tutorials on the method here and here.
The problem is that free-lensing with a full sized DSLR lens on a micro 4/3 body leave quite a bit of a gap for dust to sneak in on your sensor.
Timothy built a sweet and quick free-lensing adapter that stops both the light and the dust from creeping into the sensor. The adapter is built from a hollowed out rear lens cap and a bicycle inner tube. The two flaps keeps the light and dust out while hand holding that lens.