Dotlet was written by Marco Pagni and Thomas Junier, form the Swiss Institute of Bioinformatics in Epalinges, Switzerland.
The reason why we wrote dotlet is that we needed a diagonal plot tool for the December 1998 practical sessions in bioinformatics at the Institute of Biochemistry. Since we had decided to base all the practical sessions on the World-Wide Web, we needed a program that would run in a web browser. To our knowledge, there was none, so we wrote it.
The Dotlet source code is available free of charge for academic users. The distribution is in ftp://ftp.isrec.isb-sib.ch/pub/software/java/dotlet.