Gridraw is a simple but efficient UML drawer from Japan. It's based on spreadsheet and drawing implements, specially designed for software engineers, just in order to facilitate them to draw UML models/diagrams.

ChemPlot is a simple, lightweight but functional chemical formula building & editing tool from Czech Republic. Whether you are a student or a teacher, and no matter you are in the production of courseware or writing papers, it can equip your work with chemical formulas written by our own hands.