Here's a tip I was made aware of recently that I thought I'd share (though I'd like to take credit, I must give that to some Smart Friends of mine); it'll help speed up your Mac, and may reduce the appearance of the SPOD (the rainbow cursor). It's not a hack, and there are no modifications necessary to any of your software; there's nothing to download, and there's a fringe benefit (subjectively speaking, of course) of cleaning up your Desktop.
The tip: Reduce the number of icons on your Desktop!
That's it. Really. No, really, try it and see. If you only reduce it by a few, you probably won't notice much of a difference, but the more you remove, the snappier it will feel (dependent on your machine, of course).
Why? Well, every icon on your Desktop is a little window, and as such, has a corresponding backing store allocation in the window server. Lots of these little windows apparently can put a strain on the window server, especially when you've got lots of other (normal) windows open as well.
Don't believe me? Well, you can see for yourself, by running Quartz Debug found in /Developer -> Applications -> Performance Tools (assuming you have the Developer Tools installed -- you do have the Developer Tools installed, don't you?). Show the window list (Tools -> Show Window List), order by Application, and click on the various Finder entries to highlight each "window." You'll soon see that each desktop icon is treated as its very own window. See, I told you so.
No no, no applause necessary, cash donations will suffice...
[robg adds: I thought we had something similar in the archives, but I couldn't find it. Using Quartz Debug was somewhat enlightening for me; I don't have a ton of icons on my Desktop (about 10 or so), but each one clearly uses up a chunk of memory. I didn't notice any speed bump from reducing the number, given the small number I had to begin with. However, I suspect that if your desktop looks like the landing zone for 400 daily flights of icons and folders, then you would see a nice speed bump -- if you fall into this category, and try working with a clean desktop for a bit, please post your experiences.
For those who don't have Xcode (Developer Tools) installed yet, I wrote a very detailed how-to for Macworld a while back...]
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