So far the only thing I regret about staying up late coding is something that I'm not entirely sure is my fault.
In _Mastering Perl/Tk_, they clearly use \n as a newline when printing to a Tk::Text object. Thing is that they're printing actual quoted strings, and I'm printing from an $entry variable.
I don't think that should make any difference, but it seems to. Review under way to see if I made some lack-of-sleep typo or something, though.