I recently had my ADSL limit Capped. I am not a power user and when I checked my usage stats I found that there was usage on my account on days when I was out of station. I use World online as my ISP. After speaking to around a dozen people at WOL and telkom , I got hold of a really helpful person at Telkom who agreed to investigate. He then informed me that my ADSL account was being used by somebody else on another exchange. I spoke to WOL who would not give me any more info but changed my user ID immediately. For most users a 3GB limit is fine and if you are going over limit contact your ISP and check if your account is being used by somebody else. ADSL does not limit multiple users.