Tools used accounting/billing

Hello All.

Can anyone suggest tools to use for gathering statistics for billing
purposes? I would like to know what tools are most common among ISPs.

Thanks,
Michael

I maintain a list of free/OpenSourcish tools at:
http://inet-ops.stealthgeeks.net/software.html

(additions welcome)

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                               Patrick Greenwell
         Asking the wrong questions is the leading cause of wrong answers
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