577. Skype and webcam on debian wheezy: black screen

This is another shameless re-posting of a solution published by others. See e.g. 
http://community.skype.com/t5/Linux/Webcam-is-not-working-on-skype-with-Ubuntu-12-04/td-p/858418
https://bbs.archlinux.org/viewtopic.php?id=95388
http://ubuntuforums.org/showthread.php?t=966882

Why am I doing this? Mostly because this blog doubles as a notebook where I can write down solutions that worked for me so that I don't find myself scouring the internet over and over again for the same solution.

I hope that I'm adding a bit of value by providing step-by-step solutions and snazzy screenshots though.

The issue:
even though the camera is working fine there's only a completely black picture in skype (not underexposed -- just plain black):

The solution:
Use LD_PRELOAD to load the 32 bit V4L library (which you need to have installed -- use apt-file to find out what package). You can either start skype from the command line, or make changes to the launcher, either via main menu  as shown in the screenshot or by editing ~/.local/share/applications/skype.desktop i.e. run skype with 
env LD_PRELOAD="/usr/lib/i386-linux-gnu/libv4l/v4l1compat.so" skype

 At this point starting skype + webcam should be a happy marriage:

(aside from exposure, white balance etc. etc.)