SleepyHead is released under the GNU GPL v3 License. Please see below for a note on giving correct attribution in redistribution of derivatives.
It is built using Qt SDK (Open Source Edition), available from http://qt.io.
It also uses QuaZip, by Sergey A. Tachenov, which is a C++ wrapper over Gilles Vollant's ZIP/UNZIP package http://sourceforge.net/projects/quazip/
Redistribution of derivatives
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I created this software to help lessen the exploitation of others. Seeing my work being used to exploit others is incredibly un-motivational, and incredibly disrespectful of all the work I put into this project.
If you plan on reselling any derivatives of SleepyHead, I specifically request that you give due credit and link back, mentioning clearly in your advertising material, software installer and about screens that your derivative "is based on the free and open-source software SleepyHead available from http://sleepyhead.jedimark.net, developed by Mark Watkins (C) 2011-<current year>. "
It is not enough to reference that your derivative "is based on GPL software".