I've been using Blender for close to 20 months and I just came across that most usefull command (select at least 3 vertices before using it).
It does not appear in the doc AFAIK, not even among the shortcuts.
Please note that Shift-V recieved a bugfix yesterday that now makes it work with rotated meshes.
Life is what happens to you when you're busy making other plans.
- John Lennon