Broadband speed data logger

I am looking for a simple background application that will run on my computer to test the upload and download speed of my Internet connection. This application should test every X minutes (set by user) and sale the data in a data file along with date and time. It would ne nice to have a graphical display and avg data for the time period. Maybe there is something out there already. I'm open to suggestions. Would like a simple application that does not need an installer, simply run for current location and prompt for a file data location in which to store the new data. Please specify the language you plan to use and any other details you feel that may effect this bid process.