You'll have to use your imagination for some of these photos. It's hard to take a good picture of a window!
Seven7h House on the Left has a great post on "frosting" glass with contact paper, and you can even download their template for free.
What you'll need:
window cleaner and a rag (to clean the glass)
clear contact paper
fine tip permanent marker
I already had a roll of clear contact paper so all I needed to do was print the template. Because our window has four panes, I had to scale the template down to 85% so it would fit better. When I got to the edges I used an x-acto knife to cut off the excess contact paper.
If you've got a few hours and a roll of contact paper, this is a quick and affordable project to dress up any window. And if you ever get tired of it it peels right off. We're pretty pleased with the result so I think it's here to stay.