Looks like it'll be a lot of fun.

I just uploaded five shots I took with my new filter:
http://www.flickr.com/photos/theogb/

Regrettably it's too small because I put in the size of my camera's lens, 28mm. However, it's made for a camera where you can screw the lens in so I'm going to try to swap it for the largest they've got so I can just hold the filter over the end of the lens.

Not sure it'll really come into its own until the summer's here, though.