The new hero Draven has an ability called Spinning Axe, when used on your next auto it will launch your axe at them and upon contact the blade will deal damage and bounce back to a random location allowing you to catch it. You can have a maximum stack of two spinning axe (duh, you only have two) by repeatedly catching the first one and until the CD is back up.
The exploit here is that when you use spinning blades on a turret it does not use your stack and constantly refreshes it so you can have a bonus of 85% AD for the entire time you are attacking the turret, and a stack of two ready for any engage.
Hypothetically you could also use the turret to extend your stack duration when you have the enemy pushed to tower.