Lombardi's makes a
great clam pizza. It's the sort of thing which if you are
open to new things, you'll love it.
No tomato sauce. Just dough, some cheese and spices, and TONS of clams. Never seen so many clams in such a small area. And it tasted great (especially if you like clams, obviously).
We (myself and my brother) ordered one large pie, which was plenty. The cost was $22 I think, which is not that much when you consider just how many clams there are on a slice. Well worth it.
The "normal" pizza at Lombardi's is above-average, but not sensational. I prefer John's in Greenwich Village.