There are Tcl scripts available for this task. Hunt through the Tcl script section of egghelp.org
Some people call Tcl script's modules.
Computer Science. A portion of a program that carries out a specific function and may be used alone or combined with other modules of the same program.
In the case of eggdrop, we call C components that are not required at run-time modules. Yet in the dictionary definition above, it clearly states, that a Tcl script could be called a module.
actually they're sub-modules, as they dependant on a module to run them (well, not that tcl support is actually a module in 1.6, but the theory is sound). Thus they're probably best called script modules