I like void staff for the long range poke of Q and but lich bane is better for burning towers and if your going to be constantly getting dived the bonus to your auto's is good for a bit more sustained damage.
Or if your an upfront ballsy TF that tries to catch people with yellow cards (surprisingly good initiate to catch people out but hella dangerous).
I think I ate a bowl of mysterio's for breakfast this morning- Spiderman, Spiderman 2 WOAH!! I'm sensing 14 Mega-Fonzies!!!!-Futurama