Mine are modest compared to others, but these are my favorites suites:
Sheraton Grande Laguna Phuket - Two story villa on lagoon, semi-private pier for arrival by boat after check-in (paths from the front door for getting around to resort), patio on water and second story balcony w/water view. Bonus outside shower/ large soaking tub.
Sheraton Marina San Diego - Full suite w/ three distinct areas: bedroom, sitting room with couches and full 8-seat dining table area. Great view of the marina.
W New York - Junior suite with outside balcony on high floor. Nothing too fancy, but for a first time visitor to NYC being able to sit outside and watch the city move by was fascinating.