This is exactly what I was looking for. Great Extension for 2010, I saved a "Guides.reg" file in the same location as the extension so I don't have to keep remembering where to edit or what color I wanted. My Registry file is below in case others want to double click a file instead of traverse regedit for the location.
EDIT: Paul Harrington wrote another plugin that configures this within VS2010 itself (click on his name to see it)! Why not just build it in, who knows. But there is a way to get to work without registry editing, so the review below is not valid anymore (and I gave it the 5 stars this extension deserves).
----- Original Review Below -----
If there's ever been a feature that should have been built into the VS product it's this one. It's a must have.
Having said that, this extension is an example of why people hate programmers. Would it have been such a big deal to make the configuration integrated into the extension? For Pete's sake, this extension merely reproduces a _hack_. Why modify the registry in order to get it to work? Is it supposed to be some sort of IQ test so dumb people cannot use it?
Anyway, I give it a "4" because of the hand registry modification required to get it to work. But this is must-have functionality for VS2010. Download it and install it (and configure it) as if it was a 5+ rating.
THe description of this extension is unclear. It mentions that this is an undocumented feature, but glosses over the fact that using the Registry entry apparently stopped working in VS 2010 (version 10), AND that you need to download/install the extension to make it work for 2010.
My experience: I used regedit to add the "Guides" entry and set its value. It didn't work, so I closed VS and reopened it. It still didn't work. I logged off and logged back in. It still didn't work. Then I downloaded/installed this extension, and when I started VS again, it worked!
This is just too useful that I felt I had to explain what was missing: the actual reason to install this extension.
The VS 2012 edition is published at http://visualstudiogallery.msdn.microsoft.com/da227a0b-0e31-4a11-8f6b-3a149cf2e459?SRC=Home
The easiest way to get this is to search from within VS 2012's Extension Manager. Go to Tools/Extensions and Updates..., then click on "Online" and type "Editor Guidelines" in the search box at the top right of that dialog.
Using proportional editor font and tabs for identing, this tool set incorrect line positions (far away of the cursor position).
Also not works when the cursor is in an empty line without any text.
So it is very hard to set up the editor lines, and even harder to remove them!
The latest version works all right for me.
When you use a proportional font, the editor's column indicator switches to a sub-cell resolution in order to be able to express the unevenly spaced positions in integral numbers. Then, your best bet is to write down the column number that is displayed in the status bar at the moment of guide creation and later hunt it with e.g. tabs and spaces.
To be able to place the insertion point (and, hence, a guideline) past the end of a line, you need to tick off Options/Text Editor/All Languages/General/Enable virtual space.
Hope this helps.
It took me awhile to figure out why this extension didn't seem to be working properly.
If you use multiple guides, the registry value format for this extension is slightly different from that of previous versions.
For VS2008 and earlier, if you wanted guides at 80, 100, and 120, the registry value would be: "RGB(255,0,0) 80 100 120"
For VS2010 (with this extension), the registry value would be: "RGB(255,0,0) 80, 100, 120"
Not putting in the commas will cause the extension to not draw _any_ guides. If you use multiple guides and tried copying your VS2008 registry value, it would appear as if the new extension simply does nothing.