Comment by vincent-manis

I use Tk routinely in Scheme; there is no Tcl in my code, but Tk is a very nice (though basic) GUI kit, and my programs work on Linux, BSD, MacOS, and Windows. Other commenters have mentioned that Python ships with Tkinter, a library module that interfaces to Tk. I believe Ruby does the same. Hell, if you're programming in Cobol, you can have Tk (as long as your Cobol allows you to call C). You do not have to love Tcl to love Tcl/Tk.