I was thinking about posting a similar thing - however I'm thinking that the graph annotations could easilby be expanded to also be a general "draw on the graph"-tool. Instead of just having text with arrows I would like to be able to draw circles and rectanges - and put comments either within them or have the already existing text with arrow point to those. We often have users that want to comment on trends and then print them as reports...but currently they have to move the data from the LV apps to e.g. Excel or Word and then add the graphical elements and comments. If annotations were just a little bit more than just the text with arrows - we could skip having to make a drawing tool for graphs:-)
I've used the 3rd party TeeChart graphing component at http://www.steema.com/ with Delphi for other applications. It is capable of doing what you want and much more with plenty of control of many properties including event firing. There is an ActiveX version that maybe could be integrated into LabVIEW.
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