Mike called Eleven in episode one at 7:40 p.m.
7+4=11
Hopper promised to come back to Eleven at 5:15.
5+1+5=11
Mike's final call to Eleven was in episode two, on day 353.
3+5+3=11
Bob was haunted by a clown as a child, and his family's from Maine, so he would have been a child in Maine in the 1950s...which just so happens to be the setting of It. Bob called him Mr. Baldo, which is also a word you could use to describe Pennywise's great big dome.
Plus, Sean Astin played Mikey in The Goonies, and Finn Wolfhard, who plays Mike in Stranger Things, also starred in It. COINCIDENCE?! We think not.
Bob wondered if there was pirate treasure at the center of Joyce's giant map. Sean Astin, who plays Bob, was in The Goonies, which was about a bunch of kids finding pirate treasure.
Also, Bob died, which Goonies aren't supposed to say.
Kim Fields, AKA Tootie, tweeted her delight at discovering a nod to the Mrs. Butterworths commercial she starred in as a kid.
"THANK YOU @Stranger_Things WOW! Honored &thrilled my 1st gig would b remembered like THIS! #mrsbutterworths THX @ThefutureEP 4the heads up!"
Just after Eleven escaped to go find her sister Eight, her mom's TV was playing Action News 8.
Then Eleven rode a bus labeled 422.
4+2+2=8
Finn Wolfhard said "Holy s--t, what happened to you?" in It. Then he said it again in Stranger Things! You can see a video in this tweet from @UpsideDownFacts.
Hopper can always be seen wearing this blue braided bracelet, which David Harbour confirmed to be Hopper's daughter's hair ribbon. In the season two finale, Eleven is seen wearing it at the school dance.
H/t to @babysittersteve who destroyed us all by noticing this little fact.
Guess how many entries there are in this gallery, including this one?! Did we purposely make some adjustments to make it all add up to 11? You'll never be able to prove it! So spooky, y'all.