I disabled Akonadi & Nepomuk on one of my MDs, as well as changed swappiness to 2 (it was the default 60, which doesn't make sense to me on a machine that net boots. The core should stay on 60, in my opinion). I didn't want swappiness at 0, because I didn't want it to go completely adverse to swapping, just way lower. It seems to run a bit snappier, although I can't quantify it... largely because the machine is a dual core with 4GB RAM, and likely doesn't swap much anyway. I need to try it on the one Atom N270 MD (Asus eee Box 202) I have to see if there's a real effect there.
Another change I might make is to the fstab,... maybe using the relatime parameter (close to the noatime mounting parameter, but more mindful to logging file access). I haven't looked at the fstab to see how it is mounted now,... but if it's set to do a lot of logging, switching it can reduce the back and forth traffic on the network,... maybe, that is.
PS: Oh,... I uninstalled Kontact, which is apparently installed by default, since it, or even the digital clock in the KDE tray, forces Akonadi to start if run... KDE developers should really reconsider enabling these services by default. They really soak up system resources.