What are some fun things that work in shared hosting environment? I have a shared web space with php and SQL (MariaDB).

I plan to set up a proper home server at some point, especially since my NAS is due for an upgrade. But until then, are there some cool and fun projects to try out, besides the usual WordPress and CMS systems? I have set up FreshRSS and Shaarli, as well as Nextcloud.

Any other ideas would be great.