A neutral density (ND) filter dark enough to create long exposures in the middle of the day usually cost over $200. The photographer, Chris Nachtwey, discovered that the same effect can be achieved using a piece of wielding glass. The article/story circulated most of the photo blogs. I found is on SLR Lounge (http://www.slrlounge.com/create-ten-stop-neutral-density-filter-long-exposures).
Considering I have nearly pulled the trigger on a big ND filter multiple times, I jumped at the chance for a cheap option. Amazon once again proved it has everything (http://www.amazon.com/gp/product/B0086ANLC0/ref=oh_details_o02_s00_i00?ie=UTF8&psc=1). The shade # indicates how dark the glass is.
On Thursday afternoon, I took my new ND filter out for a test drive. I set up on a bridge overlooking a busy intersection. The glass attached directly to the lens using rubber bands hooked onto my lens hood (http://instagram.com/p/lNxDh1sTjW/). The camera can not focus through the dark glass. Consequently, focus and then switched the lens to manual prior to attaching the glass. My first couple of shots were overexposed but I dialed it in within a handful of exposures. In the bright 2:00 pm winter sun, a 30 second exposure (at f22 ISO200) was long enough to create a fun image. Right out of the camera, the images have an odd green tint from the glass.
All you need to do is convert the image to black and white to cure the color. Overall, I was really happy with the result considering I only paid a couple dollars for the wielding glass. Probably going to see a lot more long exposures now.