I only noticed how low my iMac's memory was getting when Time Machine failed to back up for the first time last week. I now have a larger external drive and that has taken care of backups for the time being. However, I have not been able to identify why my available memory seemed to suddenly take a nose dive. As far as I can tell, I have installed only two major software suites recently, Logic Studio and Final Cut Express. This morning I had only 48GB of memory left (300GB from new). Deciding I didn't use Logic that much I decided to lose this and try and regain some memory. After dumping Logic and reinstalling OSX I have regained exactly 4GB. I don't get it.... What's eaten my memory? Can anyone tell me how I can go about identifying how much memory my apps are using? Also, is there a convenient way to see how much memory is being taken up by documents, photos and movies (short of listing all the contents of all folders and adding up by hand)? Is there a free tool anywhere that allows me to quickly see where my memory is going?