Seems everywhere I surf on the net, I see adverts for "MacKeeper". They claim it to be the most popular software for Mac on the planet (slight exaggeration). But when I look at it on Macupdate-dot-com, it is rated very very low. Anyone have any experience with this App? Sounds good on the surface, but 180+ low ratings makes me wonder. I'm just curious what folks here experienced with it think?