Are you the type of person who always has their phone on silent or vibrate? While it sure beats having your phone blare out notifications and ringtones at inopportune moments, it can be a real pain in the arse when you misplace it. No you can't 'just call it', it's on silent. Or can you? If you have an Android with an associated Google account, you may actually have a chance.
While I set up Where's My Droid on my first phone for situations like this, I failed to do the same with subsequent phones. Unlike most apps that you install when you need them, apps like Where's My Droid require you to install them before you need them. Luckily, Google has an answer for those who aren't so forward-thinking.
It's called Android Device Manager, a small toolset that connects with all devices associated with your Google account. Presuming your device is able to connect to the internet, Device Manager can find your missing phone and from there gives you a few options for recovering it. First, Google gives you an approximate location (mine was accurate to within 7 metres at one point), and from there you have the option to either remotely lock the phone, permanently erase its contents or ring the phone at full volume for five minutes -- even if the phone is on silent or vibrate.
Device Manager is also available as an app, if you have a spare device to use it on. The app also allows you to help a friend by logging them in in 'guest mode'.
The best thing about Device Manager is that it's opt-out -- meaning it's probably enabled for you even if it never crossed your mind to set it up. If you do want to change the settings, you can opt out of the option to lock and erase, or you can disallow Google tracking your device's location (or both). This setting is found under 'Security' in Google Settings on your Android.
But while it may be a privacy concern to let Google know where you are, it's arguably better for your privacy to have the ability to remotely lock or erase your device. Still, if you need Device Manager, you now know where to find it.