Calcsy has a fairly simple license, listed below.
Calcsy license, version 1
Calcsy is freely available software. You may make copies of Calcsy, and distribute unmodified copies of Calcsy in any manner you wish. You may not charge any fees for copies or use of Calcsy. If you have any questions, please contact the author via Calcsy's website at http://calcsy.com or http://calcsy.lardbucket.org.
A further disclaimer: This software is provided by the copyright holder(s) and contributors "as is" and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the copyright holder or contributors be liable for any direct, indirect, incidental, special, exemplary, or consequestial damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interrpution) however caused and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such damage.