My (unique) passwords are always more than 25 characters, and it really irks me when websites place maximum limits on the length.
Worse still is when they don't even tell you about the maximum limit, so you paste your 25+ character password in, fire the registration form off thinking everything is fine, only to find they'd only taken the first 10/15/20 characters and the full length password you gave them doesn't work.
Sometimes that's ok, but not always a good sign for how they store passwords.