For a while now Eclipse has seemed a little sluggish when it starts up, and in general use. There’s no way I’d want to stop using it and the excellent CFEclipse plugin so I had the idea to deactivate Aptana and Flex Builder, and what a difference it makes!
I guess I’ll turn these back on if and when the need arises, and for now I’ve installed the much smaller XML Buddy plugin to replace the XML Editor functionality provided by Aptana.
Just go to the “Help / Manage Configuration” menu to change the status of your plugins:

CFEclipse’s tabbed editor is great, but occasionally I do make the schoolboy error of editing the wrong file, easily done when you’re “in the zone” and have 3 or 4 circuit.xml or index.cfm files open.

The “Link with Editor” option is a great way to show which file you’re working on by highlighting the file in your project tree. I hadn’t enabled this option on my new MacBook and had forgotten how I’d done it on my old machine, so after digging around in the Preferences for a while I noticed it’s actually on the Navigator toolbar itself. If you haven’t found this either - switch it on!