Oooh. Good one. Can't believe I forgot it! I too stayed a lot at the Carlton both before and after re-watching this film. It's neat to see what is the same and what has changed.

The Four Seasons Beverly Wilshire hotel (which at the time was a Regent) was prominently featured in Pretty Woman.

If the proposed Fatty Arbuckle biography movie comes to fruition, San Francisco's St. Francis Hotel will play a prominent role (it was the site of the debauched party that caused Arbuckle to be falsely accused of murder and rape, effectively ending his career (although he was acquitted)).

Don't forget Hostel :p