Android: Silence is a free utility for Android that will change your ringer, notification and other alert sound settings automatically based on a schedule you provide. For example, if you want the ringer off when you go to bed at 10pm and automatically on again at 6am when you wake, Silence can do that for you.
Once installed, just add as many actions as you choose, select the days of the week and the times of day you want to use as triggers and what actions you want the app to take. Silence can toggle Wi-Fi, Bluetooth, airplane mode and ringer settings. Set your schedule, tell the app whether you want the settings changed back to default at the end of the time period you set and enable it. Silence's beauty is in the fact that it's fast, free, easy on the battery and simple to use.
Obviously, advanced users can get the same effect out of tools such as Tasker and Locale, but if all you want is scheduled sound and notification changes, Silence does the trick, for free, in an elegant and easy-to-use package. It's perfect if you're looking for an easier way to control these settings, or if you know someone who would love these features but aren't interested in paying for or getting their hands dirty with a more advanced app.