Dream of a world in which magic humours float, coloring the air and granting temporary powers to those who walk through them.

Evasive, probably. You couldn't walk through them on purpose, that would be too easy, but absent mindedly walking along just might do the trick. You might be able to catch one even while it was executing evasive maneuvers. Would Donald Trump or Bill Gates chase a humour? If the reward was big enough, perhaps.

Color is no indication of the gift the humour grants. Cherry blossom pink might give the power to warm up a cup of coffee or to slay tall buildings with lightning bolts. You might never discover the way to unleash the power before it goes.

The powers are temporary. Whether they last an hour or a day they dissipate in time. You can't keep them.

When you walk through a humour, there is a tingly feeling as the power invades your nervous system.

Studies have been done; it appears that the powers reside in the upper spinal cord, vertebrae C5, C6 or C7. This is sort of confirmed by the fact that all known activation of a humour has been by gesture. The gestures are consistent: to make rain after you have acquired the rain making humour, you put your hands in the air, wiggle your fingers and bring them down toward the earth while taking two steps backwards. Many web sites and wikipedia catalogue the known gestures. There are only about two hundred of them.

There is a group of people, semi religious, who choose to ignore the humours. The people who ignore the tingly feeling and do not attempt to exercise the humour, self report greater happiness than those who do not. There are studies that confirm this. (In this world there are always studies; the ones I cite have been peer reviewed and reproduced. I may mention some intriguing preliminary work which offers interesting speculative lines of thought, but I will try to identify these as such.)

Living in a world where an arbitrary person might cast a love spell (touch heart with both hands and spread them outward towards the intended victims; the humour seems to know the persons intended by the spell caster, but the victims do have to be present, in line of sight and along the general direction the palms are facing) has the effect of making everything a bit lighter; a bit more exciting.

Even Donald, receiving the power to color things with lime green polka dots (dip a hand as if into a can of paint and cast the paint at the intended surface), might succumb to temptation: if not a Trump Tower, perhaps a competitors building.

Dream of a world, find the magic in the world and fly.

Or at least paint your competitors buildings with lime green polka dots.