Combine ANY active, a passive, and slap it on a champion.

Diana Passive, Udyr R, on Jax.

thwunk thwunk SMASH

tryndamere's passive on yi? if that's what you mean. If you mean actives from items too, give him mercurial's active.

Actually one better would be katarina's passive on karthus with protobelt active.

chogath ult+ sion w passive on tahm kench

evelyn Q plus Annie passive on, hmmm, yasuo

passive and nasus q on thresh

Isn't there a way to give someone infinite scaling?

Aatrox's passive on Tryndamere who has GA. Also a zilean and kayle standing next to him xD

Oooh, this seems fun. For this, I'll assume that the passive + the active are on one ability, and that it replaces one of the champ's existing abilities.

passive + ult replacing ult

passive + E replacing ult

passive + W replacing Q or E

passive + E replacing W

passive + E replacing W

passive + Q replacing E

passive + ult replacing W

I'll prolly come back to this tonight, but right now I've gotta get ready to go dancing! <3