One video it's better than a thousand of images and a million of words.
boxersoftware.com/powercolumns.swf

This option it's on some very good other editors too.
http://www.ultraedit.com/support/tutorials_power_tips/ultraedit/column_mode.html

Hi, I'm returning to NuSphere website from time to time to see which improvements phpED is getting in each new version. One thing I will appreciate a lot it's this kind of column edition. I tested 8.1 but it seems there it's not yet implemented. I don't see which things are new in 9.0 but it seems this column edition it's not announced.

I discovered months ago Notepad++ has this column edition too, but even better, with CTRL+click you could put so much cursors as you need and they could be in differents positions (not only in columns)
https://plus.google.com/+notepad-plus-plus/posts/ePAxY4ykBMm

+1