Chrysalid Software - description from Softdepia.com:
Chrysalid is for the Internet Cafe owner. It automatically controls the amount of time a Cafe client spends on a workstation, based on how much they have paid. The software is designed for 32-bit Microsoft Windows® Platforms, and provides centralised administration of workstations on a network. This system is ideal for businesses that charge their clients based on how much time a client wants to spend on a workstation. Key features of the system are: A totally prepayment-based regime. A client can only use a workstation for a period not exceeding what they have prepaid for. Keyboard and mouse locking ensures that no workstation is useable until the administrator has assigned a client time on it. Our keyboard/mouse locking routines are pretty effective we find. Not even the usual CTRL-ALT-DEL sequence will work! Centralised management and monitoring of workstations. The chrysalid administration interface is able to tell you which workstations are up and running at any time, which ones have been down and at what times, etc... Detailed sales statistics so you can track how much money you are making. New Support for skins with a future option of customised skins.
Chrysalid Software is a "Free to try" program. You can download and try it for an evaluation period.