Evil, an appropriately named automated service by Tom Scott, searches the many public notes and groups on Facebook that resemble something along the lines of “lost my phone!!! need ur numbers!!!!!“.

The thing is, most people don’t realize that they are posting something public on Facebook which means that anybody with an internet connection can see it (they don’t even have to have a Facebook account). So if you’ve ever made one of these types of posts, you better double check your privacy preferences.