Users connecting via IPC$

We have 3 machines in our Finance Dept, that are getting IPC$ connections to them. I set up NETWATCHER to monitor this. They are running Windows 98. For security reasons, files sharing is disabled. One machine which showed up as connecting, we went to it and saw no indication that the machine was connecting to the finance machine, but it showed up as such.

What is causing these IPC$ shares to show up as active connections?

Thanks

Paul