While you will need to be connected to your Android smartphone or tablet, you will soon be able to find your phone with your Android Wear smartwatch. Simply say 'Ok, Google. Start. Find my phone' and your phone will ring at full volume.
Google stated that this functionality will roll out to all Android Wear devices over the next few weeks.
My wife regularly misplaces her phone in the house and Android Device Manager has made me into a hero many times. Android Wear support will making finding a phone even easier than logging in on a web browser and I look forward to checking it out.