Bist stands for bidimensional structures
Bist stands for BIdimensional STructures (in Italian it sounds like "beast" in English) and is a chemical drawing tool. It is focused on organic chemistry but it may be useful also for chemists or teachers.
Bist supports many of the formalisms used to describe molecular structures like single bonds, double bonds, stereospecific bonds, charges, resonance arrows, lone pairs, and so on.
It can export both in PostScript and PNG formats.