During looking for a suitable tool to run Tcl in a browser I found Tcl in Javascript also named JsTcl. I found it interesting but with too few features from Tcl, so I decided to enhance that. JsTcl is an implementation of a Tcl interpreter written in Javascript and the parser is based on Picol. An implementation in Javascript has the big advantage, that it is running on most browsers, also there are some incompatibilities to take care of between the browsers. One advantage is, that you don't need to compile and link and besides the browser incompatibilities you don't have to worry about the platform you are running on.
(Part of itcl in Javascript Paper)