I've created quite a few articles. The keyword here is created, as the topics I edit about are very contemporary, so oftentimes someone else comes along and expands them. It's the beauty of Wikipedia of course, that over time articles become more comprehensive. I'll list off some articles which I actually developed, I feel like that's a higher bar than just making an article and letting other people expand it.
For anyone unfamiliar with the Good Article process, it's a great way to learn how to improve articles on Wikipedia. Basically, you submit an article to be reviewed against the good article criteria,[note 1] and another editor will come along and review the article. The reviewer will bring up any concerns they have about the article. You'll have a week or two to address those concerns, and if they're all resolved, the article will get a little green plus sign next to its title.
Here are four articles that I brought to good article status:
The other side of the Good Article process is reviewing articles that get nominated. I've reviewed quite a few articles. You can check out some of them: