Under Win32, no transparent background is needed (and no DirectX either), as the SetWindowRgn() call allows to specify a complex region as the window border. I can't find a good example to copy online, but it would be raw GDI calls and I'm not sure how to manage the region memory that gets owned by GDI after the call - I suppose one would have to keep the structure alive as long as the window handle is valid.

In principle, this should be possible from Perl, but it will be hard to find a toolkit that supports it natively. One could hack it, as long as one gets to the hWnd of the window. A problem with this approach is, that many windowing toolkits destroy and recreate windows at various stages, so the "funky shape" might get lost when hiding/reshowing the window or minimizing/restoring the window. Also, the window metrics will most likely become unusable.

perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ;    # The  
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new   #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' #  web
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