I believe the LG Quick Memo toggle in the notification bar can do the same thing. At least it does in my G2.
Yup, that's exactly what it does. it takes a screenshot and allows you to edit it, then gives you the option to save it to the gallery or the Notebook app. Pretty sure you can run it out of the notification bar as well.
If you’re a Mac OS X user who frequently uploads screenshots, … more
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