Lorance After discovering Vim (specifically GVim) has Tool Tip support thanks to its balloon functionality I wrote a plugin for Tcl. It displays Tool Tips for TCL Commands, Variables and user procedures. The current buffer is scanned for user procedures, and their documentation, every time the buffer is written. I has been extended to support not only Tcl but also AWK, with easy support for new languages.
Screen shots are available in the Github Wiki.
Initial version if anyone is interested in playing with it.