5am Pacific Time

The emptiness and lull in activity experienced by extreme internet-junkies and gamers during the early morning hours after everyone else has either gone to bed or is getting up to go to work, so named because this is when servers typically shut down for scheduled maintenance. This term transcends the local lull in activity experienced by people who stay up all night partying, having the distinction that no matter where you are in the world or what schedule you keep, and no matter how many different time zones the people you interact with are in, if you are on an English-speaking website you're probably going to experience a noticeable drop in activity around those hours.

Oh man, where'd everybody go? Just a moment ago I was having amazing conversations in like 15 different browser tabs and now nobody is saying anything! Must be 5am Pacific Time.