Doug Lawty posted at Weblogs@ ASP.NET a very useful tip: don't press Alt-PrtScn to get a clipboard copy of the content of a messagebox (as a image), instead use simply Ctrl-C (just text)! It also works for .NET messageboxs like the Rss Bandit About box:

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About RSS Bandit
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RSS Bandit 1.2.0.114 written by
* Dare Obasanjo Obasanjo (www.25hoursaday.com/weblog/)
* Torsten Rendelmann (TorstenR, www.rendelmann.info/blog/)
* and all the active members of RSS Bandit community.

Credits:
* Mike Krueger (#ZipLib)
* Chris Lovett (SgmlReader)
* SandBar Copyright (c) 2004 by Tim Dawson, http://www.divil.co.uk/net/
* Portions Copyright ©2002-2004 The Genghis Group (www.genghisgroup.com)
* sourceforge.net team (Project hosting)
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OK
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But maybe that's little bit too much to just get the version number copied