Local Video/Music: mythtv with fanless minipc for front end.
email: (sendmail/spamassassin/dovecot with Thunderbird front end)
sharing/collaboration: Nextcloud
Chat: Matrix/Synapse with Element web for the past year or so, Openfire (XMPP) for at least a decade.
Ad block: pi-hole
DNS: local recursive resolver (BIND)
spell/usage check: langtool (minimal usage, but interesting)
torrents: deluge/deluge web
proxy (forward): squid (mostly to cache fedora updates)
Podcasts: podgrab (just installed this based on an HN story a few weeks ago. I like it!)
Firewall: Netfilter/IPTables on fanless minipc
I was also running a Diaspora pod for a while, but got rid of it. I may go back to it at some point.
Streaming: Currently I use a Roku stick for this, but have been playing around with kodi and jellyfin. I hate kodi. jellyfin is pretty cool, but can't handle large music collections (jellyfin server crashes when trying to load my 20,000+ music tracks).
I won't use them for video, since both seem to think that I should organize my video files (10,000+) according to their strictures (TV vs. Movies, etc.) rather than allowing me to maintain the organization I've used for decades (genre). What's more, using their clients, I'd likely need to transcode many videos, whereas my mythtv front end (via ffmpeg) handles just about any format I throw at it.
Now that I think about it, I self-host everything and eschew any "cloud" (read: someone else's servers) services, as my data is mine and how/when I use it is my business, not anyone else's.
I just wish that more developers would focus on ease of installation[0] instead of docker containers or rafts of non-standard dependencies, which would allow less technical folks to self host this stuff -- incentivizing a broader ecosystem for FOSS and self-hosted stuff.
[0] https://news.ycombinator.com/item?id=30783477
Edit: Fixed list formatting.