A few weeks ago, I was working on an illustration and I noticed that the Divide function in my Pathfinder palette was not working the way it was supposed to. After a little troubleshooting, I found out that it was because one of the shapes I was trying to divide was not a closed path. I looked to see if Illustrator provided an easy way to find and select unclosed paths to no avail. It seemed to me that you should be able to find it under the Select menu where you can select stray points, all text objects, same fill or stroke color, or same blending mode etc. It seems like selecting all unclosed paths would be a pretty common query. Nope.
I did a Google search to see if anyone else had this problem or knew something that I didn’t. I ran across a free plug-in that adds Open Paths as well as 17 additional object types under Illustrator’s Select menu. It is awesome. Now I can easily select Guides, Open Paths, Closed Paths, Filled Paths, Unstroked Paths, etc. instead of spending valuable time and sanity hunting these rascals down.

The screen-caps above show Illustrator's Select Menu without (left) and with (right) the SelectMenuCS3 Plug-in.

You can find this and many other useful Illustrator plug-ins here. Thank you Rick Johnson! Download the file and then drag the plug-in into Illustrator’s “Plug-ins” folder. (On the website, it says it only works with CS3 and CS4 but it works for me in CS5).

The above plug-in only finds open paths. It is up to you to close them. I found a script that will find and close all open paths in Illustrator. I found this one on vectips.com. It actually contains 2 scripts; one that closes all Open Paths and one closes all selected Open Paths. To use the scripts, in Illustrator, under the File menu go to Scripts then Other Scripts… and navigate to the downloaded script and click Choose.

A dialogue box will open and let you know how many open paths it found and ask you if you want to close them all.

If you want your scripts to show up automatically without having to navigate to find them, store all your scripts in Illustrator’s Scripts folder. You can find Illustrator’s Scripts folder here: Applications/Adobe Illustrator CS5/Presets/en_US/Scripts.

Sweeeeeeet.