When something seems too good to be true at first, but then it turns out that someone just made a major fuck-up and inexplicably wants you to capitalize on it.
Example 1:
Friend 1: So, I can go to as many movies as I want for $10 a month? That's less than the price of one ticket!
Friend 2: What the fuck? That sounds too good to be true!
Friend 1: Actually I just read online that they're burning through VC money and are about to go bankrupt, and they inexplicably STILL want us to register and use the service!
Friend 2: I mean, damn, that is a Moviepass moment right there. Let's register for that shit.
Example 2:
"I'm getting paid for every line of code I write. My boss is encouraging me to split my lines into smaller lines, telling me I'll get paid more for each one. What the fuck? I'm having a real Moviepass moment right now."