I like how much a long exposure changes a scene, smooth water and a slight movement of the clouds really creates a nice effect. Anyway click here for a faster shutter speed version to compare the different effects but you can decide..
Captured at Midway Point (just near the Hobart airport) with a Canon 5D II, Canon 17-40 and B+W 110. The filter allowed me to pull a 4 minute exposure even though it was still relatively light, cooool.
Amazing what a difference a bit of extra exposure can do to a scene