Okay, I have had my iMac for several years now and it has been upgraded through Leopard, Snow Leopard, and currently to Lion. It is a 2 GHZ Core 2 Duo , forget how old... maybe 4 years now. It has never had a clean install. So before the new OS drops this summer I was thinking I wanted to clean it up but it occurs to me, how do you clean up a Mac? I have no uninstaller type programs, I have always just dragged an app from Applications to the trash to remove it. I assume this leaves stuff behind in Library both at the user and system level? When I look at login items, there are 2 items there that are marked as "can not find" which seems to me as an indication that stuff was left behind in removing applications. So short of a complete wipe and rebuild, what other clean up options do I have? Are there trustworthy and decent tools out there to look for junk? What other advice is there? Thanks!