Just created a couple of workflows to control my Philips Hue lights.
The IP address in the Alfred scripts needs changing to your bridge IP address.
Hue Add Alfred Support
This adds a user called alfredcontrol on your Hue bridge, this only needs to be run once and can be disabled in the workflow window once run, you'll need to press the button on the bridge too.
http://dl.dropbox.com/u/2013925/Alfred/Hue%20Add%20Alfred%20Support.alfredworkflow
Hue
This turns the lights on or off, I have 3 lights ( the 1 to 3 in the script ), if you have more modify the script to suit.
http://dl.dropbox.com/u/2013925/Alfred/Hue.alfredworkflow
See http://developers.meethue.com/index.html if you want to get a bit creative.