Architecturally speaking, what are your three favorite skyscrapers?

Question:

Architecturally speaking, what are your three favorite skyscrapers?

Mine, and I've seen/been in all three:
1. Transamerica Pyramid, San Francisco
2. GE Building/30 Rockefeller Center, New York
3. John Hancock Tower, Boston

Best Answer - Chosen by Asker:

The Chrysler Building, NYC, a great example of art deco
The Tribune Tower, Chicago, Raymond Hood's masterpiece
The Transamerica Pyramid, San Fran.