Hi-- I know it is an old computer, but the MBPs (and MBAs) just aren't where I want them to be for me to see an upgrade as desirable, and I don't believe that the frequently annoying but not disastrous slowing down that I experience on the machine warrants an upgrade (or ought to warrant one--given the likely engineered cause of that slowness). So, does anyone have tips specific to the Spring 2007 aluminum/non-unibody MacBook Pro on the topic of speeding it up in today's world? The details: Mine is a 2.4 GHz with 27 out of 150 GB HD available, 4 GB ram, a moderate amount of clutter on the desktop, and lots of open safari tabs. I'm experiencing slowdowns when many tabs are open (with google books, pdf articles) and when I have Word running at the same time. This is exacerbated when Aperture and/or iTunes are also running (which both have large libraries taking up most of my HD) I have a number of folders full of very big PDF books (10-200MB/book) that I keep on the desktop. I use the desktop as a way of thinking by arranging things I'm reading. How can I make this old scratched-up warrior thrive in the marathon until my next upgrade?!