Brodie says "Would you like a chocolate covered pretzel?" He said the same thing in Mallrats.
The pseudo Scooby gang have a heavy Buffy/Angel link. "Fred/The Guy" is played by Marc Blucas, Riley in Buffy. "Shaggy/The Dude" is played by Matthew James, the demon Merl from Angel. "Velma/Bookish girl" is played by Jane Silvia, who was in the first episode of Buffy series 4, playing "Conservative Woman". The only person who doesn't have any link is "Daphne/Redhead beauty", played by Carmen Lee (Jason Lee's wife from 1995-2001). Although if you're really going for tenuous Angel links, she was in a film called "Cowboys and Angels" in 2000.
In the scene with Tracy Morgan (the Hollywood dealers), if you look closely at the union cards, the president & secretary signatures, they appear to be signed by Kevin Smith and Jason Mewes.
At the beginning of the movie Jay and Silent Bob are singing Jungle Love and the 2 little kids buying the weed say "What the hell are you singing?" Jay answers back "You don't know Jungle Love? That sh*t is the mad notes, written by God herself and handed down to the greatest band in the world, the m*therf*ck*ng Time." God herself, an obvious reference to Dogma and God being a woman.
When Jay And Silent Bob are in Hollywood and running away on the bikes (after the "Good Will Hunting 2" shoot), you can see an actor wearing a Daredevil costume rolling out of the way. Ben Affleck hadn't yet signed to Daredevil, but Kevin Smith is a big fan and had written several Daredevil comics. These are available in a collected edition with a foreword by Ben Affleck, again long before he signed up to be in the Daredevil movie.
In the DVD release, the second disc contains an error. It is in the TV spots of the Bonus Material. Two of the TV Spots are misnamed. The first is the one entitled Cake. In actuality the next one labeled Justice should be named Cake and vice versa. The Cake spot mentions nothing about cake and is mainly composed of Shannon Elizabeth's character named Justice. The second TV spot named Justice ends with the scene from inside the van when Ali Larter's character pulls a knife on Jay and Jay replies "What's with the knife, we having cake?"
When Jay and Silent Bob go to Holden's house, he greets them with, "Look at these morose motherfuckers right here. Looks like somebody shit in their cereal." Jay said the exact same thing to Holden in the diner in Chasing Amy.