One photograph can contain several virtual knickknacks. I usually don't use sticky notes, as I also make a mnemonic to relate the character to the story. For instance, a story about the beach could use '@' as a conch shell, or '*' as a sea star, or '$' as a sand dollar, or '~' for ocean waves.

But everyone has their own tricks for remembering things.

And I certainly don't make the effort for sites that I don't consider to be important. Those as often as not just get reset via e-mail whenever I forget my password.