Dropbox expiring old passwords
dropbox.com
dropbox.com
Luckily, there is nothing stopping you from just entering the same password again, which is what I did.
The two main passwords I remember are my dropbox password, and my keepass password (the keepass db is stored on dropbox). They are both long and complicated passphrases, and I have managed to burn them into my memory. Don't make me do it again "every so often" because you've decided my passphrase is no longer good enough.
No company should be dictating passwords to paying customers, full stop.
I am currently a paying Dropbox customer. Please rethink your policy.