The Gateron Clear switch is the lightest linear switch currently available, with an actuation force of about 30g - half that of a typical membrane key switch and 50% less than the Cherry MX Red linear switch. It's not a particularly popular switch, because it's so light that the weight of your fingers tends to cause accidental keypresses on the home row. Nonetheless, you can buy a KBParadise V60 keyboard with Gateron clears. The Qisan Magicforce 68 is occasionally available with Gateron clear switches. Alternatively, you could buy the keyswitches and build a keyboard to your own specifications using a bare keyboard PCB.
Seconded Gateron Clears (though I've heard the activation force is more like 35g than 30g). I use them on a Noppoo Choc Mini.
I'm a fast typist (around 130wpm) and use these switches just to try to improve speed, rather than anything relating to health. They're also great for gaming for me, playing Starcraft 2.
I'm a fast typist (around 130wpm) and use these switches just to try to improve speed, rather than anything relating to health. They're also great for gaming for me, playing Starcraft 2.
Another option around 35g is non-mechanical electro capacitive switches in the style of Topre, e.g. https://www.nizkeyboard.com/product/plum-84-ec-mechanical-ke...