Is there a common place to post and download files developed for the Mac OSX Grapher application (in Utilities)? I am aware of the .gcx files at http://y.barois.free.fr/grapher (a very helpful Grapher site) but wondered about other archive locations. I attached a .gcx file I recently developed for Grapher 2.5 in OS X Mavericks, along with a screen shot of Grapher showing the equations and resulting 3D rotating intertwined tube. I learned how to do it by reading the documentation (English or French) at the site mentioned. The attached .zip file can be unzipped by opening it with the "Archive Utility" program. Then open the resulting Lissajous.gcx file using "Open With Grapher" (to see "sure you want to open it?" and answer "Open") instead of opening using a double-click (that just says "You can't open it" without an option to open it anyway).