Random Adventure Generator

ThemeAction/Adventure
This is the most common and straightforward sort of adventure there is. In the Action/Adventure scenario, you present your characters with a task and then confront them with obstacles to overcome in order to accomplish the task successfully.
GoalClear Name
The name of one of the characters or an NPC has been sullied and the characters must clear it. The characters must find out a) why the name has been smeared, b) who is responsible, and c) why the responsible party is doing it; then they must find evidence to convince everyone they're telling the truth.
Story HookMistaken Identity
The hero could be mistaken by one villain for another villain involved in the master plot. This has good comic potential if the hero and missing villain are in fact so similar that no one can tell them apart. (This is even more fun if they turn out to be long-lost twins.)
PlotAccumulation of Elements
In this sort of plot, the heroes have to go from place to place -- perhaps covering very little area like a city, perhaps roaming the known world -- and accumulate elements to be used against the Master Villain. These elements may be clues, pieces of an artifact, evidence, or allies.
ClimaxChase to Ground
First, you have the Heroes Chasing the Villain. The villain, after a series of encounters with the heroes, is running to safety, to some place where he can acquire more power, or to somehwere he can accomplish some dread purpose such as assassination or mass murder. The heroes chase him, have to deal with the obstacles he leaves behind, and finally catch up to him before or just as he reaches his goal. Here, we have the final duel between the villains forces and the heroes. Second, you have the Villain Chasing the Heroes. Often, in a story like this, the heroes have found out how to defeat the villain -- such as getting to a particular temple and conducting a particular ritual. The villain chases them all through their quest, catching up to them just as they're commenciing their ritual; they must, with heroic effort, conclude the ritual while suffering his attacks. Third, you have the Master Villain's Sudden Escape Attempt. This takes place in adventures where the Master Villain's identity is unknown until the end. His identity is revealed and he makes a sudden bolt for freedom; the heroes give chase. This usually results in a dangerous foot-chase through nasty terrain -- such as across rooftops, through the dungeons, or across an active battlefield.
General SettingOn the Sea
Most of the action occurs on the sea -- the heroes are shipborne for some reason, docking in lots of ports. Again, this is good for adventures where the heroes are investigating clues left all over the map, are part of some trading enterprise, or are being pursued by villains.
Specific Setting ICaves of Magical Folk
These can be either beautiful, glittering homes of gorgeous magical peoples, or the dank and terrifying lairs of horrible monsters.
Specific Setting IIMilitary Encampment
This is best used in an episode involving warfare; it could be the good-guy army's encampment, from which the heroes launch their adventures, or the villains' encampment, in which case the heroes might have to sneak in on a mission or escape from it if they're captured.
Master VillainAvenger
This villain seeks to avenge some wrong he thinks he's suffered. He may be right; he may have suffered a wrong, and this makes him a little more sympathetic than villains who are purely evil. The Avenger uses his organization -- thugs and bribed officials -- to get at the one who wronged him, and will want either to duel (singly) the one who wronged him, or to put the wrongdoer in a deathtrap.
Minor Villain ICoward
This character is an ordinary grunt minion of the Master Villain, but he's a coward. He's deathly afraid of the Villain and the heroes. He's best used when you plan to have the heroes captured; by his mannerisms, you can make it clear to them that this fellow is a coward and they will begin to work on him psychologically.
Minor Villain IIChildhood Friend with a Dark Secret
This Minor Villain is like the character of the same name from the Allies and Neutrals section. However, the heroes find out early on that he's really working for the Master Villain. He may not wish to be helping the villains; his family may be held hostage, or he may just be too frightened of the villain or otherwise weak-willed to refuse. Alternatively, he could actually be evil now.
Ally/NeutralMerry Minstrel
This character follows the heroes in order that he might find inspiration for his song and storytelling. He can't be shut up; he sings all the day long and into the night, is a showoff before crowds, and is far too noisy for a party trying to remain unobserved.
Monster EncounterKing Beast
At some point in their adventure, the heroes run across a King Beast -- some enormous, intelligent monster (which speaks the Common tongue) which is the leader of its species. Perhaps it needs help; if the heroes help it they'll earn themselves a favor which the King Beast will repay at some later time in the adventure. Perhaps the heroes are in deadly danger and need help; the King Beast can be persuaded to help, but only in return for a deed or favor in the future.
Character EncounterBureaucrat
Some time in their adventure, the heroes must deal with the local government and run into that most horrible of nuisance monsters, the bureaucrat and his red-tape dispenser. The heroes don't have the right forms. When they have the right forms, they forgot to fill them out in triplicate. And so on.
DeathtrapMutually Assured Destruction
In this very nasty deathtrap, the heroes are bound up in such a manner that any one of them may get free of his bonds -- but when he does, all his friends perish. Obviously, the heroes' task is to find some way for everyone to get out alive. Perhaps an intricate series of cooperative rope-cutting will defuse the trap; perhaps a coordinated maneuver will get everyone free as the trap is being sprung.
ChaseEndurance
The Endurance Chase is not some sort of climactic chase -- it's a rugged, tiring, persistent pursuit that tests the characters to their limits. In this chase, the heroes and villains are pursuing one another across a lot of territory and they're not catching up with one another very fast. This may be a horseback pursuit across a hundred miles of savannah, a camel chase across several days' worth of desert, or a chase across arctic tundra.
Omen/ProphesyHero Fulfills Prophecy
This is the most useful sort of prophecy. In the early part of the adventure, one of the heroes discovers that he fulfills some ancient prophecy.
Secret WeaknessSecret Embarrassment
Finally, the villain may have some aberration or secret shame that will force him to flee when he is confronted with it. It could be something as simple as the fact that his nose is too big, or that he is a small and nebbishly wizard pretending to be some vast, powerful demonic power. When his shame is revealed, he is too humiliated to continue; this is a good option for comedy adventures.
Special ConditionMagic Doesn't Work Right
If the adventure is taking place on an alternate plane, then that plane's magic works oddly or not at all. (A spellcaster will find that just making himself useful is a challenge when none of his spells works.)
Moral QuandrySaving Quandry
Finally, another classic quandry puts the heroes in the position of choosing between a grand opportunity to hurt the Master Villain -- or saving the lives of a number of individuals.
Red HerringLoony who Has It Wrong
You can have the heroes "aided" by a so-called expert who is actually a lunatic who doesn't know anything about what he's talking about. Once he's led the heroes off to some remote part of the continent, his evasive answers and bizarre behaviour will alert them that he really doesn't know anything about what he's pretended to be an expert on.
Cruel TrickWanted by the Law
One final complication, one which occurs pretty frequently, is when the heroes are wanted by the law. When they're wanted by the law, they have to travel in secret and very limited in the resources they can acquire.

Based upon tables from the Dungeon Master's Design Kit by TSR, Inc.