The lights are on
Pressing a button and having a console simply start up isn't an option these days. Device functions must be punctuated with an awesome sound effect that sounds like it's ripped straight from Star Trek. The new Xbox 360 Elite S system makes neat little 'ding' sounds when you turn it on or open the disc tray, and now you can download them for free for your phone.
Hop over to the blog of Xbox Live's Major Nelson and get to downloading. The sounds are available in iPhone format or MP3.