Ones I've been to:
US (no particular order):
San Francisco (old Van Ness, and new - not nearly as friendly - Pier 39 location)
New York City (57th st)
Las Vegas
Boston
Outside the US, in order of visit:
Sydney
London
Paris
Edinburgh
Pattaya
Bangkok
Singapore
Got T-shirts at all of the international locations except Pattaya; only NYC and Las Vegas for the US ones. I've also got a HRC Tel Aviv T-shirt - never been, but it ended up in mixed up laundry back in college.