I just re-read article from earlier in the year on evolt.org again that outlines 10 tips to make your pages load faster. I like to re-read stuff like that to remind myself of the things I am getting lazy about.

Some highlights:

1. Avoid tables for layout.
2. Don't use images to display text.
3. Call up images through CSS.
4. Use contextual selectors.
5. Use shorthand CSS properties.
6. Minimize white space, line breaks, and comment tags.
7. Use relative paths instead of absolute.
8. Remove unnecessary META tags and META content.
9. Put CSS and Javascript in external files.
10. Use '/' and the end of directory links.

Many worthwhile tips for sure. However some of them, while good practice, start falling along the lines of small enough that you'd not see too much impact - so don't go spending several hours going through old code to add a '/' on the end of all your directory links or anything - just start adding them from now on ;-)

While great tips, some won't save you a whole lot on performace - but still good practices. Others however, such as avoiding tables, will give you real benefits and considered best practice.