The absolute lightest tool I have that packs the most punch for its size is the Bottlebug. It’s very thin compared to most Atwood tools but is strong for its weight thanks to the use of high end stainless steels by Crucible. It’s called the Bottlebug because it’s designed to be a very lightweight bottle opener that sports some other functions to boot.
What kind of people would write collect and review multitools? Quite simple really- we are designers and do-ers, outdoors types and indoor types, mechanics, doctors, problem solvers and problem makers. As such, we have, as a world spanning community, put every type, size and version of multitool, multifunction knife, pocket knife and all related products to every test we could manage in as many places and environments as there are.