[flippyhead]

I feel like we can all just jump at the same time. I mean, we only need a second or two, right?

[ninju]

Well...we would all have to be at the same spot so that we don't cancel each other out. But that would come with its own challenges

https://what-if.xkcd.com/8/

(oh and it wouldn't be strong enough to affect the Earth's rotation)

[slashdave]

Maybe a whole bunch of people can charter some planes, fill them with weight, and just travel full around the earth to where they started.