I got tired of having to come inside to change the song that was on Spotify, modify the volume, etc. I couldn't find any good iphone apps to do this for me, so I wrote this thing that runs as a webapp you can access from your iphone.
The main file runs on the same machine as Spotify, and basically just receives web requests, executes applescript that does the actions you tell it, queries information from Spotify, etc, then renders HTML for an iphone.
At first I tried writing it in PHP and just running on Apache, but doing that means that whatever applescript you execute runs as the Apache user, which (rightfully) doesn't have permissions to touch Spotify. So instead I wrote it with Tornado in Python.