For the last couple years I've done a lot of hacking with the Qt framework using it's Python bindings. Initially I used PySide to build interfaces in Qt4 for little processing scripts to automate things I and my coworkers were doing manually in Excel and notepad. When Qt5 came out with Qt for Python things got even easier and more fun. I starting hacking around on my own time. Qt Corner is a collection of minimal scripts I've written to showcase some widget or feature of the Qt framework. A lot of times when I need a GUI for a program I can start with one of these simple scripts.
Drop me a line if there is a particular corner of Qt you'd like me to explore.
Folks often seem hung up on the licensing of the Qt framework. I admit that recent changes with Qt 6 seem a bit concerning. But my understanding is that most of the Qt framework is under the LGPL and as such I can use it freely in my programs (for any purpose, commercial or otherwise) so long as I don't modify the Qt libraries I use AND so long as the Qt libraries are dynamically linked to my program. For my development process (Python, Qt for Python, PyInstaller in folder mode) this license works just fine.
The Qt 6 license change means that while the latest Qt 6 versions remain open sourced, long term support versions are available only to users with a commerical license. I'm torn about whether this is big deal or not. For developing simple offline, native applications, I think I can continue to use Qt 5 as-is without bug fixes. It's pretty solid at this point. If I was developing something as important as, say, KDE, I'd be pretty concerned. But more generally, I really like Qt and want it to continue to be developed and available, which means I want it to have a steady revenue stream. TLDR: I'm still waiting to see how things shake out.