Is the 'building' on top of the cake plastic or cake? Any thoughts on recreating this cake?
http://www.ssb4.net/users/13325/spiderman_spin_kick__2.jpg

I cant tell, but you could easily make gumpaste panels for the sides of the building, or fondant panels. use a dowel for the stick that spidey is hanging on.

It's one of those plastic cake toppers they sell at the cake supplies stores

Those look plastic but those can be achieved using gumpaste/

I'm sure it's plastic to but could be "easily" achived with gumpaste