MaskedNinja is an email scanning service that protects you by scanning and alerting you when you receive emails that contain malicious URLs and / or other types of threats on the Internet. This secure, easy to use, fast and reliable service is completely free for all users. Users are required to register for a free MaskedNinja account in order to use the service. Users can also sign up using a Google or Facebook ID in one click. The service automatically scans email for malicious URLs and threats against multiple public databases and returns the results to users in just a few seconds. MaskedNinja's deep scan engine scans for hidden links,  shortcuts, as well as image links, that may lead to a known or potential threat.