I'm always fascinated with survival techniques that yield surprising value from (sometimes) unexpected resources, like dew collection and Super Shelters. That's why the Warka Water project caught my eye.

There's a YouTube user who goes by "Colhane" who has spent a lot of time in the wilds of Brazil, and his channel has a huge amount of great info. In this video he demonstrates dew collection while on an overnight in a dry grassland area of Brazil. You can see that in those conditions, tying 2 or 3 rags on a stick can gather a surprising amount of water but you need to be able to treat it.