After watching episode 8x05, I had an idea to make my own garage door opener since my remotes were all broken. I wanted a small device that didn't need the use of a computer web server to operate. My research led me to making an Arduino based device, with an AsyncLabs Wishield and my own circuit to control the garage door switch. I created an iPhone app that talks to this device to operate it.
Parts came to around $100, so I would say its cheaper than buying those universal remotes.
I documented everything at http://wifigarage.com. I created a video of it in action as well http://vimeo.com/16314199.
Let me know what you guys think. This was my first iPhone app and first micro-controller experience. It was definitely fun doing it!