My new laptop runs REALLY cool, so I only turn it off to update or reset. My old one however, ran really hot, and I turned it off pretty often. If I leave it on I put it on a cooling stand so it doesn't overheat.
i just about never turn mine off, its always waiting ready to go when i get home or get up, every so often it dose updates and restarts over night, that pisses me off cause i lose everything i had open for quick links, and i get confused as to why it appears to have restarted.
when i know im not going to be home for a few days and i dont have downloads going, i shut it down, then i get confused when i return and have to switch it on, i always forget it takes a bit of time to start up and rember where everything was or what i had open before.
as for my laptop, no just about never unless im taking it somewhere outside of home.