Speeding up Linux

I'm a happy Linux user and like to tweak my operating systems to get as much performance out of them as possible, though not at the expense of sacrificing too much user experience niceties.
This article posses 7 Ways to Speed Up Your Linux Desktop which in a nutshell are:

1. Use a Minimalistic Window Manager/Desktop Environment
2. Customizing GNOME, KDE, or Xfce
3. Get More RAM
4. Kill Unneeded Processes
5. Remove Virtual Terminals
6. Use “Small” Applications
7. Remove Start-Up Services

Like I said, I still want a nice user experience, so I'm sticking with KDE and Firefox for my browser (for many reasons, not the least of which is that I can synchronize bookmarks and plugins across multiple computers and OSes for a common Internet experience). However, the other tips can be useful.