My late 2008 MB (aluminum) runs a 2GHz Intel Core 2 Due and has 4GB of RAM (it came with 2 GB; I upgraded to 4 GB about a year into ownership). I run a free program called Memory Clean, which monitors the amount of free memory available. (The app is available in the App Store if you'd like to take a closer look.) Within the past few months I've noticed that I'm burning up 4 GB of memory and need to "clean" it for a boost. When my memory gets low, performance starts to suffer/become sluggish. Is this a common issue? Is there something I should be doing differently? I was always under the impression that RAM was not a significant consideration for Macs vis-a-vis Windows PCs. My recent experience seems to contradict this. Thanks in advance for any thoughts.