Simple & Great Rated 5 out of 5 stars
I've been using it for years now and it still serves me well! Unobtrusive and simple: just prefix with @@ or F2 and your password will be a hashed one specific for this site.
No more worries when a site leaks all of the unsalted passwords (like linkedin recently did).
Just two things on my wishlist:
1. adjustable salt/password length via options
2. highlight password form field, if PwdHash is active