My main Xojo program is a business database front-end for my indie software business. It parses sales notifications and inserts them into an offline database (ie so no customer data is ever kept online). It has a business dashboard for key performance metrics, generates charts for various sales / demographic queries. It also lets me generate serial codes for customers when giving away copies of my apps in promotions. I've been using that for about 20 years.

I also made a cross-platform Twitter-esque client (similar to Tweetbot) to work with the Micro.Blog social network. I had it fully working with Mac, Windows and Linux before I got disillusioned with Micro.Blog and didn't release it.

For internal use, I made a project estimation app for solo/indie developers like myself, that uses Monte Carlo estimation to predict an actual ship date based on the (in)accuracy of your previous task estimates. It had charts of percentage confidence, so you could give an 85% or 95% confidence of shipping a milestone by X date. The tasks & milestones were structured like an outliner and could be moved just with keyboard navigation. It was able to load project files from a discontinued Java program called Mr Schedule that I loved. That Xojo app was cross-platform Windows & Mac too.