It’s the simplest planner available. Users type plain-language commands into Coolendar—no need for precise syntax—hashtagging keywords to organize similar tasks. For example, “Monday, 5 p.m., don’t forget to pick up the #dry-cleaning.” Coolendar automatically slots these into a to-do list and will send Gmail and Google Talk reminders. The free site syncs with other calendars and has an app for smartphones.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.