One of my players gave me eleven adventures from Goodman Games Dungeon Crawl Classics line for D&D 3.x Sunday. I've glanced through several of the adventures for lower level characters (Idylls of the Rat King, The Mysterious Tower, and Legacy of the Savage Kings) and find them surprising good -- pretty much like an average modele from TSR during the early to mid 1980s. The stat blocks for monsters make my eyes glance over, but the actual adventures are pretty good and the dungeon areas are designed like old school dungeons with tricks, traps and monsters of assorted power levels.
Any of these adventures could easily be used in my OD&D campaign without a lot of effort. Use the monsters, but with the stats/description from OD&D. Let the player handle the tricks and traps as in OD&D. And have fun. This would also work for any other version of old school D&D. If you looked at most 3.x adventures and said too much trouble to convert, you might be pleasantly surprised by Goodman Games Dungeon Crawl Classics. At least the 3e version. Most of the modules numbered above 50 are designed for 4e. I doubt they were be as easy to convert.
The "back cover" descriptions read much like those from early TSR modules and sound just as interesting. Here are descriptions of some of the modules I now have:
Legacy of the Savage Kings (Levels 4-6)
For centuries, the Great Swamp has hidden hints of an ancient culture of barbarian kings. While passing through this miserable bog, the PCs encounter Stygoth the Damned, a half-dead black dragon driven mad by a mysterious disease. Delving further, the heroes discover that the disease is tied to the very swamp itself. A great corruption once infested this place, destroying the savage barbarian kings and leaving only mighty statues as their legacy. Now this corruption has returned, and a terrible Witch Queen is mining the corrupted swamp-earth to produce evil, blighted artifacts. In order to stop the spread of these evil weapons, the heroes must enter the ancient caves of the savage kings, put to rest the corrupt legacy of their downfall, end the disease that scars the land, and then face off against the Witch Queen herself.
Idylls of the Rat King (Levels 1-3)
In Idylls of the Rat King, goblin bandits are once again attacking the silver caravans, killing innocent miners and stealing cargo. The goblins have taken up residence in an abandoned mine northwest of Silverton. Someone must get rid of them. But this is no ordinary abandoned mine. It was deliberately barricaded generations ago when the Gannu family, founders of Silverton, discovered an unspeakable evil on its lowest levels. And these are no ordinary goblins, for the curse of the Gannu family courses through their veins...
The Mysterious Tower (Levels 1-3)
In this all-new adventure, the characters come across an ancient wizard's tower. The nearby keep has been reduced to rubble over the ages, but the tower is in perfect condition. It is surrounded by an impenetrable force field that cannot be breached - not even by the ghost of the long-dead wizard, who has been trapped within for centuries. Surely there must be great treasure within this magical abode. But how to get to it?
Temple of the Dragon Cult (Levels 8-10)
In Temple of the Dragon Cult, the characters are called in to pursue a dragon that the king's army was able to wound but not kill. It seems straightforward enough: the army tracked the dragon to its lair, and all the characters have to do is go in and kill it. But this dragon has a devoted cult of dragonblood followers who worship its every breath. Its lair is their temple -- and they'll fight to the death to defend their dragon-god...
The Sunless Garden (Levels 6-8)
After arriving at a seemingly abandoned trading post, the heroes discover to their horror that all the inhabitants have been transformed into black trees! Upon further investigation, they find clues that lead them to the hidden lair of Nockmort, a treant gone bad. Nockmort has been transformed by the strange radiation of a meteorite he discovered, and now he is a terrible force of evil. The characters must enter his sunless garden to save the town. And along the way they just might discover fabulous treasure...
The Dragonfiend Pact (Level 2)
The small town of Welwyn has been beset by a string of robberies. The heroes are led to the natural cave system located at the bottom of the town well, which they must explore to find the burglars. But once they're in the cave system, things get much more difficult! The "burglars" turn out to be mere pawns in a much darker game. To get to the source of the crimes, the heroes must shrink themselves with potions of improved reduce person and explore a series of dangerous rat warrens where their prey is larger than they are!
One thing to watch out for would be the level ratings. You have to take them with a grain of salt since they are aimed at the levels used in D&D 3.x. You'll need to look through a DCC module carefully to decide what levels it is best for in the version of D&D you are playing. Chances are they will be close to the listed level, but it's better to be safe and not trust the printed level guide than be sorry when you are looking as unexpected TPK.
Looking at these modules also gives me hope for the Dungeon Crawl Classics RPG Goodman Games is working on.