The Encyclopedia of Geometric Constructions. Is a shareware product.  It
contains 50 files (minimum) of geometric constructions e.g. ellipse1.euk 
using the file format of the Euklides dynamic geometry program www.euklides.hu
also available as shareware from  www.shareit.com  
The geometric constructions  include many complex constructions such as
geometric harmonics on triangles and ellipse and the centers of similitude of
circles of different radii to name a few.  These can now be easily used as
base constructions for new constructions using Euklides.