MicroEmacs is a cross platform text editor similar to Emacs but with a much smaller footprint. It does not use lisp as the scripting language but its own language. Micro does not mean "minimal functionality." In fact, MicroEmacs comes with support for many languages (Tcl included), automatic (smart) indentation, macro recording, spell checking, source browser (Tcl support included) and user extensibility via its own scripting language.
More can be learned about MicroEmacs via the home page: http://www.jasspa.com