If you watch NatGeo at all, you'd understand that what the Earth is going through is the NORMAL FLOW of things. All thru time the Earth has had periods of warming and cooling, warming and cooling! Before humans came along to waste all the planet's resources and dirty up the place, there was decomposition from decaying vegetation in the natural swamplands which covered the planet for millions of years - that produced carbon dioxide and a lot of other gases that hurt the ozone and fowled up the oxygen in the air.. IT'S NORMAL, people!

And NO.. I don't leave any of my 4 pc's on when they aren't being used. Better for my electric bill, better for hackers and trojans not being able to invade my space! Unless you have an older pc, starting/stopping those parts does not wear them out ANY sooner, but it sure as heck keeps them from being invaded by those bug jockies looking for an unprotected place to land. Electric parts are ALWAYS subject to fail - its the nature of electricity and electrical parts. Turn it off or suspend it when it isn't being used!