What are your favorite low-footprint self-hosted services? - Sopuli

Hello everyone! I recently switched my Android phone to a custom ROM, and while setting things up, I wanted push notifications without relying on Google. That’s how I discovered UnifiedPush. Really liking the concept, I decided to rent a small VPS (1 vCPU, 2GB RAM) and started hosting NTFY. So far, it’s been working great. Over time, I’ve added a few more services like FreshRSS and Audiobookshelf. All of this is just for personal use, so the resource usage is minimal (the whole setup only uses around 500MB of RAM). I really enjoy how much value you can get out of such a small machine. That brings me to my question: What other lightweight, self-hostable tools would you recommend? I’m especially interested in small, resource-efficient services that you’ve personally found useful. Thanks in advance for any suggestions!