build a network of trusted babysitters

One  of our small supply of trusted babysitters has fallen in love with someone in Nanaimo (hint to fellow parents: DO NOT encourage your babysitter to go visit that ex-boyfriend in another town). So we're back to searching for fresh blood, and wondered whether there might be room for a web app to help. 

Turns out, someone else has already thought this all through. CareSquare is a well thought-out online community that helps parents find available caregivers, and lets you rank trusted caregivers and see those who are trusted by your friends (or their friends). There are a few hundred caregivers already in the network, but surprise surprise they're mostly in the San Francisco area.