I have been wanting a way to automatically adjust my ringer and notification volumes to vibrate or off at night for a while. I never really thought to go look for an app to do it, I guess I was just thinking it should be something built into the OS so it never entered my mind until the other night that there is probably a 3rd-party solution. That is when I came across an app called Locale, the version I found is free of charge and available in the Android Market.
In short, it allows you to setup certain situations (time ranges or meetings in your calendar) or location awareness that in turn adjusts the settings like you’re ringer volume. You can adjust an array of things, but I’ve found a video that androidapps.com put together on YouTube.com so I’ll let it do most of the talking.