I have done a few google searches as well as some searching through instructables and have not found anything concrete about the application. There are apps that dim based on time of day (like Flux) but here in Florida, especially in the rainy season, it can get dark really quickly. There are a few apps for linux but my many forays into linux end up with me getting frustrated and removing the partition. I'm new to Instructables, but in the short time I have been a member I have seen that this site is undeniably the best on the web. If there were anywhere I would find what I'm looking for, it would be here. I have found a few interesting links: 1) Ambient Light sensors (ALS) are supported in windows 7: http://msdn.microsoft.com/en-us/windows/hardware/gg463470 2) A video by a Microsoft program lead back in 2008: Building Context Aware Applications: http://channel9.msdn.com/blogs/pdc2008/pc25 3) Here is a proof of concept for a contest. Someone has actually made a simple app. Unfortunately, it is constantly running and the UI is command line: http://sven.killig.de/BLUntrl/. It is hard to understand him as he seems to go in between German and English. I wish I knew how to program cause I would probably change the code and create a better UI. The best route to save power would probably to have the computer check every 10-15 mins or more (maybe even user selectable). So guys what do you think?