Through the View Finder is a popular type of photography right now that has some really amazing affects on images.
I've seen a couple of photos lately that have really captured my attention and it made me want to go and find out how people are doing it! I found this tute on how to do fake TTV in case you can't find a camera to use.
This is a really great idea, especially if you are like me and cannot just run out and buy an antique camera on a whim. (Though the thought has crossed my mind!)
You can also do the real thing if you are up for it! If you follow this link to Russ Morris' flickr feed you can check out his Contraption, and view some amazing TTV photos. If you are a frequent visitor to etsy you'll most likely have seen some artists using this technique. There are some really great prints for sale.
In the mean time I hope you can have some fun with this tutorial from Vimeo!