I’ve recently found and uploaded all my childhood QBasic to GitHub.
Probably one of the coolest projects is PaintPro, which is a dos-based mouse-driven application for creating colorful ASCII art. Once you have a PaintPro image, PaintPro will then do code generation and create QBasic source for embedding the image in other programs. This, like all my other mouse driven QBasic, requires libraries only QBasic 4.5 (or was it 5.1?) has, so you’ll have to find a copy of that to get this to work.
The other really cool one is my dos-based visual text editor, QBCode, which not only lets you edit files, but does all manner of variation of ROT13, except not 13, and across all visible ASCII characters.
Some especially hilarious source files:
Lastly, I want to make a special mention of ADVENTUR.BAS, since my amazing friend Paul ported it to the web so you can play it without also having to use DOSBox. Check out SONIC’S ADVENTURE 1.5 (and repo)