Looking for a work time clock?

I'm doing some 3d modeling work and I'd like to keep track of the time I've been working. I'm looking for an application that would allow me to simply click it when I start working and than click it again when I'm done. Preferably with some sort of a calendar so I know how much time I've spent working in the space of a month and on specific days.

Every time I search for that kind of a thing all I get are Iphone and android apps and I'm not interested in that.

I just use a simple spreadsheet, entering the date, the time (separate cells for hour, minute and Am/Pm), project name, project phase, and total time (calculated from the time cells).

If I'm ever asked what I was doing at a specific time and day, I have it logged; if I'm ever asked how much time I spent on a project, or on a particular phase of a project, I have it logged.

It only takes a few seconds to enter a new row of information, or to duplicate the last row and then change the details (the calculations remain intact when you copy the row that includes the time calculations).

There may be a better way, but this is quick and easy, and didn't cost anything to buy any new software.