"most users tend to re-use the same passwords, probably because they can't remember the two dozen unique usernames and passwords they're forced to have. So if you obtain their forum password, it's likely you also have the password to something a lot more dangerous: their online banking and PayPal."

I admit to being somewhat guilty of this, but I'm astonished anyone would use the same password for throwaway email acconts as for financial stuff. I do use only like 2 different passwords for all my stupid little Internet forum accounts, though.