Oh, and some neat, self-indulgent stuff like a Pulp Fiction reference and Abed from Community.
What did we see? And did you spot something we missed? Read on...
As we reported earlier today, Sorcerer Supreme Stephen Strange gets name-dropped in this film.
Strange is a character whose movie is not officially greenlit yet, but who has been "promised" to the fans for a while now, starting with an interview Marvel Studios President Kevin Feige gave in 2012.
Because what else would Nick Fury have on his headstone?
Stark Avengers Tower
Following the destruction in Marvel's The Avengers, Tony Stark's fancy new skyscraper was left damaged, with only the "A" in "Stark" standing, leaving many fans with the impression that the building could turn out to be the Marvel Cinematic Universe's version of the Avengers Mansion.
Two years later, apparently Tony has either warmed to the idea that "A" is for "Avengers," too...or he's just been too busy to get the sign fixed.
Gary Shandling's Senator Stern makes another appearance (he showed up in Iron Man 2 before this) and is outed as an agent of HYDRA.
His approval ratings are still probably better than the actual Senators from Pennsylvania.
A history lesson
A lot of fans have wondered what form an Agent Carter TV series might take, especially with Marvel's Agents of S.H.I.E.L.D. already on the air and many viewers somewhat underwhelmed. Could the Marvel Cinematic Universe continue to support a show with a poor reputation if a second one came along and stole some of its thunder?
Well, if the show goes forward, it look like it will be a very different kind of spy show, as apparently Peggy Carter was the one who founded S.H.I.E.L.D., so presumably the Agent Carter series could deal with that build-up.
Speaking of recurring characters from Captain America: The First Avenger, Nazi scientist Arnim Zola appears as a disembodied holographic head for a bit in this film...a form that should leave comic book readers feeling pretty at home.
Baron Von Strucker
While unnamed in the post-credits sequence, that's longtime Avengers villain Baron Von Strucker who delivers the "age of miracles" line. Played by Thomas Kretschmann, the character will have a major role to play in Avengers: Age of Ultron but also has been signed for multiple films.
Quicksilver and Scarlet Witch
Those tortured souls he was apparently experimenting on? Yeah, that's Elizabeth Olsen as Scarlet Witch and Aaron Taylor-Johnson as Quicksilver. The pair have bopped in and out of the Avengers lineup for decades in the comics, but are arguably best known as the children of X-Men villain Magneto. The rights are jointly held by Marvel Studios and 20th Century Fox, so Quicksilver will be appearing in next month's X-Men: Days of Future Past as well. The pair will appear in Avengers: Age of Ultron, in which Marvel cannot refer to them as mutants or to Magneto.
...And, yes, that's apparently Loki's mind-controlling, Infinity Stone-adjacent scepter we see there.
Brock Rumlow, the corrupts S.H.I.E.L.D. Agent whose face is scarred at the end of the film, is best known to comic book fans as the masked villain Crossbones. Often working with The Red Skull, Rumlow is an elite assassin for hire whose most high-profile shot to date was when he and a brainwashed Agent 13 "killed" Captain America (he got better) in a story written by Ed Brubaker. After the events of that tale, Bucky briefly retired his Winter Soldier identity to take on the role of Captain America in Steve's absence.
Agent 13, as alluded to above, is also an important character from the comics. In her case, she's Sharon Carter, niece to Cap's first love interest Peggy and, potentially, the true love of his life. During Cap's "death," she was pregnant with Steve's baby, although she miscarried before Rogers returned from the grave.
Familiar faces...in a different way.
The Apple Genius and the nerdy Triskelion soldier are both connected to Community, the cult-hit NBC comedy that brought directors Joe and Anthony Russo to Marvel's attention. Pudi stars in the series as Abed Nadir; his usual foil (who recently left the series) is Donald Glover of the Derrick Comedy group, which includes Pierson.
Hey, wait...since Abed is Batman now, does that mean this counts as a crossover?
Ed Brubaker, who wrote the comics this film is based on and is credited as the co-creator of the Winter Soldier, makes a cameo as one of the scientists working on Bucky. (We noticed this in one of the trailers.)
Captain America's got a lot of catching up to do...like, a lot.
The list of pop culture and world history events to catch up on is more expansive than it first appears; depending on what country you saw the film in, the list featured different names, titles and events. A German variation included the Berlin Wall, the French cut of the movie had Daft Punk and the English version had The Beatles (which, really, should have been on the U.S. version, too).
Iron Man and Hulk get name-dropped
The Romeo & Juliet poison that Fury uses to fake his death was developed by Bruce Banner in the hopes of keeping "The Other Guy" in check, while Tony Stark is credited with the design changes to the Helicarrier as a result of his near-death experience in the propellers during The Avengers.
Stan Lee's Cameo
Stan Lee appears here as a Smithsonian security guard who doesn't really do the best job, as Cap manages to get some of his old possessions out of there.