This post is short because the original is lengthy...
Go read Optimizing BE responsiveness if performance is of interest to you.
That's quality article Monsieur Roos. Thanks for sharing !
I hope some people will take time to comment this excellent article over there.
Patrick
increased the thing feelingly, allthough i cannot tell, that yslow is showing up as good for me, as shown in this presentation, but i guess thats partly cause i run the settings from htaccess rather than from apache conf.