I was trying to install TeamViewer, and I followed the instructions here even though they specify 11.10 instead of 12.04 (what I'm running).

In particular, I executed.

$ wget http://www.teamviewer.com/download/teamviewer_linux.deb
$ sudo dpkg -i teamviewer_linux.deb

The dpkg command failed, and after this point my packaging system has been broken. The software center instructs me to try:

$ sudo apt-get -f install

which leads to

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Correcting dependencies... Done
The following packages will be REMOVED:
  teamviewer7:i386
0 upgraded, 0 newly installed, 1 to remove and 17 not upgraded.
9 not fully installed or removed.
Need to get 89.0 kB of archives.
After this operation, 81.9 MB disk space will be freed.
Do you want to continue [Y/n]? y
Get:1 http://us.archive.ubuntu.com/ubuntu/ precise/main dash amd64 0.5.7-2ubuntu2 [89.0 kB]
Fetched 89.0 kB in 1s (83.9 kB/s)
E: Sub-process /usr/sbin/dpkg-preconfigure --apt || true returned an error code (100)
E: Failure running script /usr/sbin/dpkg-preconfigure --apt || true

At this point I'm stumped.