You should also consider wxPerl. I like it much better than Perl/Tk - BUT, I also do a lot of C++ programming using wxWidgets, so I'm pretty familiar with the wx widget library. One issue, for example, is that Tk looks like Tk everywhere. wxWidgets uses the native GUI elements for whichever environment you're running on (so on windows, it looks more like a native windows app, etc.). Having said all that, I usually make everything into a webapp, then use the browser as my GUI.
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