Sound Valley - free application that allows you to reproduce the sounds of nature (birds singing, wind in the trees, forest stream, storm, etc.) on your computer. Includes scenes editor. It is possible to run it at startup and it has auto-off opportunity in "sleep mode" by setting the time to turn off the PC. There is also a "Rest" feature, which will remind you that your eyes need rest, if you're constantly in front of the monitor.
