I am currently in that level of hell reserved for people who upgrade their GNU/Linux system too quickly. I have for some time now been happily using KDE 4 with the plasma desktop enjoying the cute little animations and eye candy, and learning to use the task-bar and widgets. Then my bliss was interrupted by a simple mistake. I decided to upgrade. I forgot that my /etc/apt/sources.list was set to load experimental versions of the software, and now my X-server system is broken. It is only now that I am discovering that there is no apt-get undo.