I have a Raspberry Pi Zero W that is serving as my Pihole server, but that only uses about 10% of its very underpowered CPU, and I feel like I'm not getting my money's worth. Anyone have any lightweight project ideas I can run on it to use up more of its resources?

Could I run BOINC limited to 50% CPU usage on it or is it too slow to complete jobs on time? Could I maybe seed torrents for popular Linux distros on it without the rather weak Wi-Fi chipset getting overwhelmed and bottlenecking the DNS server?