TkDVI is a DVI previewer built with the Tcl/Tk toolkit. It can use multiple windows to display multiple pages at the same time (which can come from multiple DVI files sharing a common font repository). Each window can show either a single page, two facing pages (as in a book) or sixteen reduced pages in the space of one, to check page breaks and positioning of floating items. TkDVI supports many features from xdvi, such as a magnification glass, but also adds interesting stuff like a gv-like page selector and a `rubber line' for measuring distances. TkDVI is based on a reusable Tk `image type' for DVI files which can easily be incorporated in other programs, and it is straightforward to customize and extend TkDVI itself.
The Freehand Formula Entry System is a research prototype for recognizing online handwritten mathematical notation, developed jointly by researchers in New Zealand, the United States and Canada. A user draws expressions with a mouse or data tablet, and LaTeX, a bitmap, and an operator tree are produced as output. Symbol recognition and expression interpretation are performed as the user draws.