Don't rely on our word that something is useful; grab the available tools and try to kick down your own virtual door. (howtogeek.com)
The Web can motivate students to read by opening virtual doors to people and faraway places that would otherwise be inaccessible to them; such virtual visits often make reading much more meaningful! (educationworld.com)
But in addition to actual door - to - door campaigning, I did what I can only describe as virtual door knocking, which was adding as many people on Facebook that live in South Orange and sending an introductory message. (inc.com)