PS. HN works amazingly fast at 64 kbps!
Besides that I'd go with some good stuff long forgotten: pure text email, terminal based web browsers, pre-downloading web resources you use often during the night (some browsers were able to do that in the '90s), IRC, etc.
When I started to use the Interned we've had ONE dial-up 64Kbps modem shared over 10 PCs :D It wasn't amazing, but everyone was able to get something valuable out of it. Now I'm sitting alone on a 1Gbps cheap fiber looking on my CHEAP router capable of 10Gbps... I've almost forgot how it is to be limited by bandwidth. But I also remember that limitations of that kind were responsible for people becoming very creative with how they use infra.