TrID - Allows to detect file type by recognition of binary signatures.
ChemDraw - ChemDraw - The Gold Standard for Chemical Structure Drawing and Research Publications.
TrIDNet - TRIDNet is the GUI version of TrID, probably more practical to use than the CLI version, especially...
ImageJ - and Other Health Care
Toolsley File Identifier - Identify files based on the libmagic database in your browser.
ACD/ChemSketch - ACD/ChemSketch for personal and academic use brings the power of our structure drawing package to your home computer.