I know that *Touch of Evil * opened with that famous tracking shot without the credts. I can’t remember if the opening credits came later or if it didn’t have them at all. I’m sure someone can come by and give the right answer.
I could be misremembering, but doesn´t Reservoir Dogs start in a similar way? Straight into the crew all having breakfast and discussing Madonna, the rights and wrongs of tipping and other such issues. After one of them pays, they get up and leave. Que dum dum dum dumdum, dum dum dum da dum dum and the credit sequence for Mr White etc
According to the Halliwell Film Guide, it’s generally traced back to Rommell, Desert Fox (1951), but he also cites The Egg and I (1947) (where Claudette Colbert lectures people about how eggs are not something to take for granted), and Destry Rides Again (1939), where there is about a minute of shooting before the credits appear.
I could be remembering wrong, but didn’t Pitch Black start that way, trying to avoid a crash landing with the ship?
The earliest cold opening of a movie that I know of is in Crime Without Passion (1934), directed by Ben Hecht and Charles MacArthur, better known as the authors of the venerable stage comedy The Front Page.
It opens with an extreme close-up of the barrel of a gun, which is fired. Blood drips on the floor. The three Furies of Greek mythology ascend from the puddle of blood in flowing robes, and fly over a modern metropolis inciting various crimes of passion. One of the Furies sweeps her arm over the face of a skyscraper, shattering the window glass, which showers down until it forms the words Crime Without Passion.
I believe **Naked Gun ** starts with a cold open. Frank Drebin saves the day before the opening title/credits.
I was wondering why his seed was seed was looking for perches. 
Or maybe he meant purchase, i.e “a firm grip or grasp, footing, etc., on something.” Definitely an obscure usage, but that was much of the charm of Hi’s (and the rest of the cast’s) flowery dialog.
I always heard it as “purchase.”
(Side note: I actually saw this movie before it was released in a review screening at my university. We had to fill out surveys afterwards.)
Super Troopers has roughly 10 minutes of action before the opening credits.
Finding Nemo has the long intro with the mother getting killed by the baracuda and all the eggs gone except one. Then they cue the title screen.
Master and Commander: The Far Side of the World has no opening credits. I think I remember hearing on the commentary that they had to pay a fee to some organization for not showing them.
The Lord of the Rings trilogy generally started out with a lengthy prologue with no credits and only a title.
The Directors Guild of America has contracts with the major studios requiring that their members be credited at the beginning of the picture; deviation from that provision imposes a fine.
Serenity
The Ring had no opening or title at all. The Dreamworks logo appeared, and briefly a staticky “ring” appeared over the D in “Dreamworks”, but that was it, straight into the action.