I'm a "two bright orange high mil thickness 55 gallon bags" guy.

These are stronger than most plastic ponchos, pack smaller than any space blanket I've seen, provide both a surface to sit on and something on top to keep me dry. They can be cut up for signalling. They can be used to carry water or anything else. They can be cut to about the same size as a blanket - typically to be used as a shelter roof.

Typically while I'm out & about I'll also have my Exped Bivy Poncho in my bag, but the 2 bags per person go whereever I (or my wife/kids) go.