I've been trying to understand how to convert images to black and white, I've tried many techniques, and I think I have a fairly basic grasp of it now.
I did a bit of searching around my archives, and I found this photograph of a sunset at the Barnet Marine Park in Burnaby that I thought would work well in Black and White, and I now present to you my efforts. (Entire gallery, including 3 attempts can be found at http://garethlewin.smugmug.com/gallery/873317)
First, the colour version
Second, the B&W version