Five Room Dungeon
An idea by JohnnFour (the übernerd that writes for Strolen's), it's a pattern for making a quick dungeon delve. Five simple steps, and you get enough for at least a session around the kitchen table, maybe two, and the heroes feel like they really earned their experience points.
The idea was so good, Wizards of the Coast stole it for the example adventure Kobold Hall in their latest work (DMG, 4th edition, pages 210-219).
Maps and stats aren't important, you can work those out after you have the sequence of the plot and challenges down. The idea is to hammer out like three or four of these while you're not paying attention in class, and then pick the best ones, polish them, and then add details later. You don't even need exactly five rooms, just five scenes in sequence.
The five rooms are: Entrance with Guardian, Puzzle/Roleplaying Challenge, Trick or Setback, Big Climax, and then Reward/Revalation.
 Entrance with Guardian
There has to be a reason why nobody else has come here before. It's difficult to get to, it's hidden, there's a guard posted outside, or a foreign big nasty decided the entrance makes for a good lair, something only heroic types could overcome. An antagonist right away gets the player's excitement up, and gets the dice rolling. (Sometimes you can switch the first and second room, if a puzzle at the entrance makes more sense.)
- The entrance is trapped.
- There's multiple entrances, but only one is correct (Tomb of Horrors)
- The entrance requires a special key or ceremony: "speak friend and enter," decker must hack the entrance.
- A guardian was deliberately placed at the entrance: golem, guard dog, nightclub bouncer.
- A hidden ambush waits in the shadows.
- A portcullis that the kobold guards can pass through easily, but heroes must expose themselves to lift.
 Puzzle Or Roleplaying Challenge
For those whose characters aren't the fightin' types, the next area lets them show off the skill points they spent in Diplomacy or Spot checks. This pleases the players who didn't pick Rangers and Barbarians, and breaks up the pace a bit before getting back to the RAWWWWRR. Be sure to allow for multiple solutions, because playing the "guess what I'm thinking" game is boring for players. Once you figure out the puzzle here, go back to room 1 and put some clues.
- chessboard floor with special squares
- a hallway of coloured portals with an old riddle telling them which way to go. (Tomb of Horrors)
- a corrupt city official can give the permits to enter the radiation sector
- the apartment building has buzzers for tenants, but the quarry is using an assumed name
- the chamber of the ark is covered in venomous snakes that will shy away from open fire
- the floor is covered in pressure-plates for dart traps that kobolds are light enough to ignore
 Trick or Setback
This is where you raise the stakes. Something about the plan has gone wrong, something the opposite of what they expected. Maybe the NPC they brought along gets kidnapped. Maybe they fight the big bad, but it's actually a minon pretending. This room is good for giving your players a second dose of fighting or puzzle, whichever they prefer. This is also a good opportunity to get players to waste some resources that could be useful in the big fight in room four, such as using up their flaming oil on a troll when a mummy is the BBEG.
- The hostages they rescued demand/plead to be taken back immediately, before the heroes can find the villian.
- You've found the lich's lair, but he seems awfully weak, and isn't he a demi-lich? (Tomb of Horrors)
- Contains a one way exit, dumping (some of?) the group back outside room 1.
- The heroes found the data they need to steal, but it's encrypted, and the password are further inside.
- One of the NPCs that came along takes the magic dingus for himself and runs off.
- The heroes walk right into kobolds playing a sport with swinging boulders from high ledges.
 Big Climax
Here's the ringleader, the goblin chieftan, the big kahuna -- Big O, it's showtime. Spend more of your effort on tactics, setpieces and showy effect on the fight in this room, because this is what the adventure module is named after.
- make a detailed map, with interesting terrain and usable props for jumping/tripping over, grabbing, swinging...
- start or end with some acting. Maybe the boss needs to stall to finish preparing, or to allow for reinforcements. Maybe there's hapless minions to toy with when their leader falls.
- The big bad is going to have powers that is beyond the monsters & traps encountered up until now.
- The lair is trapped, and only the BBEG knows how to get around the room safely.
- Previous rooms might have clues for the weaknesses of the main villian.
- The evil guy has the holy whatzit in his grasp, and threatens to destroy it.
- The kobold chief has a magic staff, a pet that steals player's gear, and a rolling boulder trap that his followers can avoid by climbing ledges and using ranged attacks.
 Reward, Revelation
Here's where you sucker-punch the players. The big fight is over, time to pat each other on the back for another great job... OR IS IT? It doesn't have to be an actual fifth room, it could be a plot-twist that reveals itself after the big fight in room four. Maybe the players will find the plot hook to the next adventure, or clues about a major plot-arc over the campaign, or maybe the REAL villian will reveal himself and twirl his moustache.
- A trap is sprung, which re-animates the big guy from room four.
- Bonus treasure is uncovered which leads elsewhere, such as part of a treasure map, or deed to some land.
- After being weakened by the fight in room four, the bad guy uncloaks from following the heroes and snatches the whatzit.
- The captured princess wasn't kidnapped, but ran away from home to elope with the bad guy. (Blackrock Depths)
- The true, gruesome meaning behind a national holiday is discovered.
- The alien's language is decyphered, revealing that the hostilities was all just a misunderstanding.
- A prophecy comes true, but not they way the players expected.
- The kobold chief was pressured into raiding the human villages by a young white dragon who demanded tribute.
- Strolen's where Jonn first writes about it.
- 5 Room Dungeons for the super-lazy you can download 19 five room dungeons already made for you.