I have a gaming one.
I reinstalled Perfect World onto my new laptop on Christmas and tried to log in, it didn't work and I was using what tends to be my username on most things, I sent a password reset several times and then in my fustration sent a customer support email. Got it back with
'Dear starrypawz,
Would you ensure you are logging in with your account name (insertname) and not your forum name" (which is starrypawz)
I also did this on WoW many a moon ago
Was doing a gather quest and it said 'you've got all the items' so I went to hand it in and it went 'you need 3 more of this item' and I was like 'huh? but it says I have them' sent a GM request, turned out the items were in my bank. ><