A free and open source multiplatform 3D parametric modeler
Surface Explorer 3D plots mathematical surfaces in 3D.
Free minimalist software for maps, import DWG, DXF, SHP, KML, GeoJSON
free simple dxf to gerber file converter
Format converting tool for genotype Data (e.g.PLINK-MACH,MACH-PLINK)
collection of illustrative programs:small games, simulators: C, Matlab