I did that when I was CIO at a non-tech firm; all IT costs for hardware, software and services (including ISP lines) were apportioned to the various floors and

I did that when I was CIO at a non-tech firm; all IT costs for hardware, software and services (including ISP lines) were apportioned to the various floors and depts by seat basis. 10 years later, my ex-CFO still thanks me for what I did, and wish I was still with the company.