SockQuest? And you called Toon silly? 
Ah, well–sock it to 'em.
Basically, what barbarian said.
My school roleplaying club like a ‘Big Bash’ for the end of term session.
The players roll up evil D+D monsters (give them a HD limit), and you prepare a party of suitable good characters.
Then prepare a simple venue (abandoned fort, forest clearing, cave complex), decide who’s going to attack who and go for the combat.
This year I’m going to have an gladiator arena*. Each player has a HD or level limit for a combat team, and generates characters, or monsters, or both. The DM makes up a couple of teams too.
All contestants have a couple of rounds to prepare (spell casting, thieves hiding in shadows etc).
Then all teams enter simultaneously!
The players will give you simultaneous orders (they don’t need to be complicated) and you can order your groups at the same time. (Some groups might find it fun if all orders were secret. They couldn’t tell each other’s units, or yours, apart).
Enjoy your day!
*what do you mean, I’m influenced by Hollywood?
Okay, yeah, it’s silly. But I find that I do humor best when I don’t start out trying to be wacky. Toon just puts too much pressure on me to be funny.
With the whole SockQuest concept, I can work in some conflict, some drama, and some character development, which will give the absurdity of finding out they have to go find a sock to save the world a bit of a counterpoint.
Thanks for the tip on All Flesh Must Be Eaten, MGibson. That sounds really, really cool. I may do that as an ongoing campaign sometime. Also, Balance, Lost Souls sounds cool. But I need something brainlessly simple.
And Bosda, you can DM me any time. Really. That sounds just too cool for words.
Oh, and Barbarian, thanks for your concern about burnout. I’ve actually been taking a DM break for a couple of weeks, as one of my players dropped out of the game really dramatically a while back. I’m still trying to figure out how to work the game around his character’s absence. One of my players has been running Feng Shuei, and doing a great job, but is also working 60 hours a week, so he needed this week off. And I really, really don’t want to go anywhere near my regular campaign until I’ve figured out what to do about my player’s sudden absence.
And a one-shot sounds like fun.
If you already have GURPS, try to find the GURPS adaptation of Bunnies & Burrows. I think it might even be on the web somewhere so you can save a few bucks since the book itself is out of print. Loosely based off of Watership Down, you all play rabbits. Rather amusing if your players are willing to set aside any dreams if munchkinism and play a rather helpless little beast beset by crows, foxes, cats and badgers. I mainly own my copy for the amusement value; I can’t imagine trying to convince anyone that they’d want to play some year long campagain with the setting, but for a single afternoon it could be worth some good times and a definate change of pace.
ESCAPE FROM DANIR’S HOUSE OF INFINITE PLEASURE.
Your team must escape from a huge harem driven to insane lusts by magics while avoiding traps, guards, std’s, and general naughtiness. Everything goes and is great for the filthy minded dungeonmaster.
“You are chained by Mistress Chapel and her loony nuns who drive 48 points off you with the mace of tickling!”
“Ouch!”
Of course, the follow up is better. RETURN TO DANIR’S where you have to go back in for some of your old characters ‘captured’ by the harem. Amazingly, you will have to fight your old characters. Why? Well duh, would you want to go?
Doing your legwork for you, here’s something to get you started:
http://www.sjgames.com/gurps/articles/BnB.to.GURPS.html
http://www.ii.uib.no/~bjornts/.rpg/BBindex.html
http://www.eusa.ed.ac.uk/societies/geas/CYCLO/B/Bunnies_and_Burrows.html
I also found information for a B&B/Wraith: the Oblivion crossover which I found greatly amusing and might have to try someday since I own the W:tO books 
It seems the original crisis has passed, but what the heck.
Fourthing or fifthing–an aye to the motion, at least–of “Paranoia”. The game’s just about designed to do one-shots with.
“Tales from the Floating Vagabond” is similarly non-serious without too much silliness, since that seems to be a concern. All those adventurers always meeting up in some tavern? The Floating Vagabond is sort of an interdimensional archetype of all those places. Characters have schticks based on what they do–one might have the Theme Music schtick, his own musical score plays whenever he enters a scene, giving him presence. Another might have the Errol Flynn schtick–he tends to have to enter and exit rooms by crashing through windows while swinging on a chandelier. And so forth.
oOOH!
I’m not the OP, but I’ll definitely have to give some of these a try. Especially B&B and AFMBE.
Zombies are cool.
Geez Opengrave, I’m glad I wasn’t the only one thinking about ground-to-ground combat…
What on earth is going on here? The thread title is about a good one-shot RPG. Rocket Propelled Grenade. Hell, they’re all pretty good but it depends on the target.
hey, MrVisible, tell us how your SockQuest went over.
i just might keep that on file, if it played out how i thought it would…
Umm… Role Playing Game.
No grenades involved. Probably.
So far, the setup is going well. I really like that system, and the figures are half-done… so it’s coming along. It seems objects that arrive in the new dimension from our world end up with strange powers. The leader of the unfriendlies has discovered how to use the sock to gain the worship and admiration of all the unfriendlies, and whip them into a warlike frenzy, in preparation for invading our world through the gate.
He’s wearing the sock as a hat.
I wouldn’t say no grenades involved. I think I have seen grenades in just about every game I’ve played. From TacNuke grenades in Paranoia (which I also heartily recomend) to Holy Hand Grenades in D&D.
Heck, if you aren’t using grenades in your current adventure you should add them. Go ahead toss a grenade at your characters (not your players). They will love it, I promise.