F.lux is a free as in beer application that alters the color of your screen. It can help people who have problems sleeping after heavy computer use. At minimum it makes your laptop feel more cozy at night.
I don't normally write endorsements for applications in this space but I had to make mention of a bit of software written by David Santiago. The idea behind F.lux is that your laptop is designed to look good during the day, at night the color balance changes around you and your laptop's color should too.
I recently moved myself to a new MacBook Pro and it's crisp display does look quite good during the day. I had found myself using the laptop late at night wanting to get a little something done. Some how, these late night coding adventures would end up stretching later and later. Recently, I looked up and noticed it was 4:30 am and I wasn't tired.
I had been told about F.lux by another MacBook Pro owner and so I installed it that early morning. The software immediately altered my screen color to a pleasant amber tint. Within five minutes I was sleepy.
I had not realized what a huge effect staring at the blue tinted screen was having on my sleep cycle. I wonder how many other professional computing people are suffering from a similar problem and are completely oblivious to it.
If you suspect you might be one of the people who like me are very effected by local lighting you should definitely take this for a spin. If David Santiago had a tip jar I'd definitely drop a few bucks in there. He deserves a beer for saving my sleep cycle.