Purpose: gather together tips on writing portable Tcl and Tk programs that will more likely run on many platforms.
Looks like someone started a similar page some time ago, calling it What should I be sure to do so my Tcl based programs run cross platform.
ftp://tcl.activestate.com/pub/tcl/doc/portable-tk.ps and ftp://tcl.activestate.com/pub/tcl/doc/portable-tk-slides.ps