If you like to eat out, you’ve probably heard of OpenTable. Nearly ubiquitous in metropolitan areas with lots of restaurants, OpenTable is a webapp that allows you to quickly and easily make reservations online. Just punch in your favorite restaurant (not all restaurants use OpenTable for reservations, but lots do), and a time, and OpenTable will tell if you if there’s a table available. If there isn’t, it can suggest nearby times, or other similar restaurants with open seats.