I searched the forums and tried Onyx and I don't know if it helped. It probably did and I didn't notice. I just got my 24" 2.8 iMac last year. I have so many files and have 60gb left. I decided to back up my files onto an external hard drive with Time Machine and then reformatted the hard drive. When I did that it felt like new and it felt really fast! I recovered all my Applications and files and now it feels a LITTLE slow. What else can I do? I am going to transfer the files I don't use a lot to the external hard drive. I am not using Time Machine anymore. (I want to use that external hard drive for something else).