Clarke - two questions

Today's USAToday has a very nice half-page appreciation article 
(written by Cesar G. Soriano, special for USAToday).

There's an in-set box titled "1953-73: A Collection of Clarke Titles",
and subtitled "Arthur C. Clarke's expansive body of work includes 
these seminal titles:".  Listed are these five works:

- Childhood's End
- The City and the Stars
- The Nine Billion Names of God (collected short stories, 1951-56)
- 2001: A Space Odyssey
- Rendezvous With Rama

It is not said why they stuck to 1953-73.

So, two slightly different questions:
1) Without the year restriction, what five Clarke works would
   you list as "seminal titles" in his body of work?
2) What are your five favorite Clarke works?

As far as I'm concerned, listing short stories is absolutely fine.

Tony, still thinking on his answers to those two questions, largely 
      because the short stories are rather out of focus