We're replacing the Forum on our site with this blog and will be posting pictures of our customer's house/mailbox numbers when they submit them to us. We'll just add a note to our instruction sheet sent with each order asking for jpgs, so it will take a while to collect any interesting pictures.
Missing or illegible house numbers don't just mean you might get a cold pizza, it could cause critical delays in EMS or other first responders finding your home. Numbers available on the web range from custom metal numbers, to vinyl stickers, to illuminated numbers, and reflective numbers.
The main thing is to have numbers, but you should seriously consider having numbers that are visible at night somewhere on you residence. For now, I'll just add a few sites that have house numbers and will provide more information in the future.
You also might want to check with your local fire department since many departments have specific requirements as to size, reflectivity, etc.