Nice thread. I'm sure I'll think of some more places as soon as I post this, but...

Just about any place I go with my wife;
New Zealand, particularly the South Island, for the scenic beauty but also the wonderful people;
Iguazu Falls--one of the the three most stunning scenic experiences I've ever had;
The Grand Canyon--also on that most stunning list;
The Annapurna trek in Nepal--the third one on the list;
The Taj Mahal--the most stunning human-made sight I've ever seen;
Paris and Venice, the two most romantic cities we've ever been to;
French Polynesia (Moorea and Bora Bora), especially staying there on an over-the-water bungalow;
Sydney and a small town called Port Fairy, Australia;
Thailand (especially Khao Lak);
Western Cape of South Africa, including Cape Town;
San Pancho (aka San Francisco), Mexico, a small seaside village maybe an hour's drive from Puerto Vallarta...though perhaps it's become overdeveloped in the few years since we were there;
London, though admittedly that's partly because I spent a year there as a student and it's the place that got me started on an international life and career; and
The San Francisco Bay Area, where I live and which from the first time I visited here I've felt is one of the best places on earth.