Just sleep it...I used to shut mine down because the lights were too bright. Now that my computer is farther away from my bed, it's sleep at night and restart for updates.
I sleep mine, I don't think its been "off" off since I got it. Last time I checked, my powerbook G4 hadn't been rebooted in over 34 days. I only reboot that when an Apple update comes out. I can't remember the last time it was completely off.
In contrast, I just got a new IBM Thinkpad T60p laptop at work. I've been leaving it on and I had to reboot it after just 4 days because random stuff started to crash Don't get me wrong, I'm not a PC hater, but man, that's annoying.