The wxWidgets Team: http://www.wxwidgets.org/whowhat.htm
http://www.wxwidgets.org
http://www.wxwindows.org/faqgen.htm#licence
"Can I use wxWidgets for both proprietary (commercial) projects, and GPL'ed projects?
Yes. Please see the licence for details, but basically you can distribute proprietary binaries without distributing any source code, and neither will wxWidgets conflict with GPL code you may be using or developing with it. The conditions for using wxWidgets are the same whether you are a personal, academic or commercial developer.
http://www.wxwidgets.org/newlicen.htm
Copyright (C) 1998-2005 Julian Smart, Robert Roebling et al
Everyone is permitted to copy and distribute verbatim copies of this licence document, but changing it is not allowed.
WXWINDOWS LIBRARY LICENCE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public Licence as published by the Free Software Foundation; either version 2 of the Licence, or (at your option) any later version.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public Licence (LGPL) for more details.
1. As a special exception, the copyright holders of this library give permission for additional uses of the text contained in this release of the library as licenced under the wxWindows Library Licence, applying either version 3.1 of the Licence, or (at your option) any later version of the Licence as published by the copyright holders of version 3.1 of the Licence document.
2. The exception is that you may use, copy, link, modify and distribute under your own terms, binary object code versions of works based on the Library.
3. If you copy code from files distributed under the terms of the GNU General Public Licence or the GNU Library General Public Licence into a copy of this library, as this licence permits, the exception does not apply to the code that you add in this way. To avoid misleading anyone as to the status of such modified files, you must delete this exception notice from such code and/or adjust the licensing conditions notice accordingly.
4. If you write modifications of your own for this library, it is your choice whether to permit this exception to apply to your modifications. If you do not wish that, you must delete the exception notice from such code and/or adjust the licensing conditions notice accordingly.