When I worked in a corporate environment where other people would actually hear your system start up, this was a popular way to identify your computer in the land of cubicle gophers. Finding ever more creative and annoying system sounds was on a level of importance rivaling the need for tacky desk ornamentation. Robin already bears witness to numerous geeky acts throughout the day, so sound effects are overkill.
To make your own system sounds, you need to first make sure the file you want to use is a WAV format file. If the sound is in any other format, you’ll need to covert it using an application like Digital Media Converter. Assuming the file is a WAV format file, open your PC Audio Properties by right-clicking the system tray speaker icon found in the lower right corner of your screen(If the speaker icon isn’t in your system tray, click Start, Control Panel, Sounds and Audio Devices). Click the Sounds tab. Select Start Windows in the list of available sounds. Browse your system to locate the sound file you want to use. Click OK. On the next system start up you should hear your new sound.