When people comes to college they have to make a prescription in one of our computer rooms. On the main page there was an input box asking for your ID Number ("Enter your ID").
Then we got a call
Student: I've entered my ID and nothing happened.
Comp. Support: Sure? Let me check, can you tell me your ID number?
The computer support guy enters the number and logs in without any problem.
Comp. Support: What was the problem then?
Student: I don't know, I just inserted my ID card in this slot (floppy disk drive), but nothing happened.
Right after he finished we had to take the computer to the lab so we could recover the student's ID card.