IFTTT (If This Then That) lets you connect all manner of social media, websites, automating processes. Their ‘Find My Lost Phone’ is hugely helpful. Email yourself with a tagline of #lostphone and it’ll call your phone with an automated message of your choice.
I also use it to text reminders, post Foursquare checkins to Google Calendar, send PayPal receipts to Evernote, and more. There are 108 channels. You can pretty much connect any channel to another channel with recipes you create. It’s still completely free. Check it out.