One of the sources of to-do's for me is through e-mail. I get a variety of automated e-mails (i.e signing requests) and lots of generic requests or questions from people I know.
I built Mail to Tana to forward those to @tana_inc and auto-extract to-do's: tana.pub/K6c7oiydQcJL/mail-to-tana-documentation
Mail to Tana includes a template with all the functionality to build forwarders right from @tana_inc.
The easiest to setup is the example, which simply puts the entire email with attachments in your Tana Inbox. It also creates suggested to-do's.
Mail to Tana runs every email you forward to it through OpenAI using your own key and allows you to customize what the AI will do with it.
It supports structuring output with Supertags and Fields. I mostly use this for to-do generation, but your imagination is the limit.
This is quite a powerful (and at time complicated) tool, more geared towards power users.
You can see how to set it up and some basic use cases in my YouTube video on it: youtu.be/R8HNF0KX0QE