I still haven't found "that" project yet :)
I'd look for something super low key and maintainable. Something that delivers actual value to, like, 10 people now and not theoretical value to 1,000,000 people in three years and with $15m in funding. Simple, maintainable projects with room enough to grow out to be complicated beasts.
For the record, this project has become a complicated beast, but it happened naturally.
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