I've been playing with the Camera+ app on my iPhone. I've taken a few photos and given them a very retro feel, which I think is pretty cool. It's nothing new - you'll see similar stuff all over the web. I added the text on my PC, not with the app.
Here are some pics of the Sportster at the drive-in:
Here's one with a different effect:
... and here's a shot of the Road King from the frigid 2011 Spring Flood Run: