FireChat may catch on as a way to corral revelers, but that's just the beginning of its practical applications. For political organizers, it could become a critically important way to keep protesters and activists connected when their traditional forms of communicating get cut off.
Desiccators are sealable enclosures containing desiccants used for preserving moisture-sensitive items such as cobalt chloride paper for another use. A common use for desiccators is to protect chemicals which are hygroscopic or which react with water from humidity.
Dementors are among the foulest creatures that walk this earth. They infest the darkest, filthiest places, they glory in decay and despair, they drain peace, hope, and happiness out of the air around them. Even Muggles feel their presence, though they can't see them. Get too near a dementor and every good feeling, every happy memory will be sucked out of you.