The trick was this: back then you'd check the associated email addresses of low ICQ numbers. If it was Yahoo, Hotmail and the like, there was a small chance tha

The trick was this: back then you'd check the associated email addresses of low ICQ numbers. If it was Yahoo, Hotmail and the like, there was a small chance that the email address expired and could be re-registered. The forgot password thing then gave you access to the ICQ account.