tkalc is a pocket calculator for developers and IP network operators. Arbitrary arithmetic or logical expressions can be entered very quickly in a text entry field. The result is then simultaneously displayed in decimal, hexadecimal, octal, binary, ASCII, IP address, and Boolean format. It accepts all number formats, operators, and functions that can be handled by the Tcl interpreter and extends this even further for input of IP addresses and binary numbers.
The GOBLIN project consists of a C++ class library for a large series of graph optimization problems, GOSH, an extension of the Tcl/Tk scripting language to graph objects, and GOBLET, a graphical user interface to the library functions. GOBLET includes a graph editor and supports the standard graph layout methods.
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.
Alana is a highly responsive Turing Machine simulator with many examples, like (unary and binary) addition, subtraction and multiplication, "copy band content", string parsing examples, and divisibility and primality testing. The documentation contains an introduction to Turing Machines as well as some interesting theoretical information (halting problem, busy beaver, universal Turing Machines) and pointers to further literature.
Finomaton lets you comfortably draw and typeset finite state machines (automata) and similar graphs. The resulting graphs are exported to plain MetaPost and can be included in TeX and LaTeX documents for excellent typesetting quality. States are magnetic to facilitate connection, and any TeX command can be embedded in the labels of states and lines.