One strategy for Angry Birds Bad Piggies level 20-8 is to fling the white bird down towards the pile of golden wrenches (just above the leftmost helmet pig). If you drop the egg bomb at the right moment the white bird’s corpse will bounce off the stationary stone and up into the middle of the top platform. With a little luck the top platform will come down and the debris will take out all the pigs below. The score in the video below is 118,820.
Note, this was previously Angry Birds Bad Piggies Level 19-8. Rovio shifted some chapters around in the v3.0.0 update. More info on the v3.0.0 update can be found here.