One night, a man named Shuichiro Kudo comes across a tiny angel trapped on a tree branch. He frees her, and in return she offers to grant him a wish. However, Shuichiro is a successful doctor, with a home and everything he needed; he declined the angel's offer. The persistant angel, named Kohaku, refused to give up, stating that "some wishes cannot be fufilled by oneself." After settling in at Shuichiro's home, Kohaku reveals her mission to track down the Angel Master of Wind, Hisui, who has abandoned heaven. That is, if her devil rival and his two catty servants would let her leave long enough to do so...
(Source: ANN)

The manga takes place after Sakura graduates from Tomoeda Elementary School, in her first year of junior high school. Sakura sees a mysterious dream, and an incident takes place.

To honor CLAMP's 15th anniversary, CLAMP no Kiseki: The Ultimate Collection features full-color pages, exclusive material, 6 pages of new, never-before-seen manga, and limited-edition collectible figures!

Legends say that when it snows, it is because the snow princess is crying. A collection of five tragic tales, all connected by the bond of snow. Shirahime-syo is CLAMP's tribute to traditional Japanese form and storytelling.

Many different oneshots published in Newtype Magazine, each involving xxxHOLiC and another CLAMP title.

Kindai Mahjong:
A short gag "series" that Clamp draws in various magazines. This one came from Kindai Mahjong, a gambling magazine. It features a certain blond bishie from Gohou Drug along with a couple of other characters from xxxHOLiC.

Kazahaya is rescued from freezing to death on the streets of Tokyo by another young man his age named Rikuou. Now Kazahaya rooms with him (who he dislikes for his attitude, even though he's grateful to him for saving his life) above the drug store they both work at, Green Drug. Both work for the mysterious store owner Kakei, while putting up with Kakei's "friend" Saiga, who is always teasing them. The strangest thing about Kazahaya's job is that he and Rikuou are often sent on "extra jobs" by Kakei ...which are different and stranger every time, be it to retrieve a book or a girls' school uniform. Kazahaya always accepts the "extra jobs" so he won't end up without money and on the streets again...but he really wonders what the purposes are of these "extra jobs".

-On Hiatus

An introspective, character-driven series, Tokyo Babylon reads like a manga version of The X-Files. Its story -- a modern-day fantasy -- follows a young onmyouji (spiritual medium) on his quest to protect Tokyo from evil spirits.
Teenaged Subaru Sumeragi is the 13th head of the Sumeragi clan. Together with his twin sister Hokuto and the mysterious veterinarian Seishirou, Subaru travels around Tokyo, calming the ghosts that threaten the city.

A new story begins with Watanuki and Yuuko, while guests wishes are granted.
(Source: LuffyNoTomo)

Akagi's one-shot drawn by CLAMP

Hikaru Shidou, Umi Ryuuzaki, Fuu Hououji are on a field trip to the Tokyo Tower with their respective schools. The girls are blinded by a flash of light and hear a voice calling for the Legendary Magic Knights to save Cephiro. They fall through the sky into another world, Cephiro. Once there, they meet Master Mage Clef. Clef explains, "In Cephiro, one's will has the ability to change reality for better or worse. The dark fears in people's hearts become monsters, while a well-intended wish can do miracles. One person, the Pillar, whose will is stronger than anyone else's, is responsible for maintaining through her prayers the well-being of Cephiro."

In the first story arc, the current Pillar, Princess Emeraude, has been captured by her high priest, Zagato. The three girls are charged with the task of saving the Princess.

Magic Knight Rayearth follows Hikaru, Fuu and Umi along with their friendly sidekick, Mokona, on their quest to save the mystical planet of Cephiro.

CLAMP School Detectives focuses on the exploits of Akira, Nokoru, and Suoh - 3 pre-teen sleuths - and their quest to make the CLAMP world safe for the girls in their class ...

[From Condensation]:

About three girls who transform into rabbits to save people from the Stress Monsters.

From Be With You Scans:
A collection of bittersweet tales of all the different shapes an unrequited love can come in. Why is it so difficult to confess your love? Why is it that another person can affect someone else so strongly? When a powerful man is fickle, he is allowed to be. But if a woman is unfaithful, she is called a tramp. Koi tells the realistic stories of six different women of different ages, and completely different outlooks on life.

Long-awaited continuation of the manga "Legal Drug" (Jap. "合法 ドラッグ"- "Gohou Drug"), by bestselling group CLAMP. It picks up from where the plot in Legal Drug left off, with a short prologue catching readers up to the main events of the previous series.
Kazahaya has always had the ability to see the memories of items and people that he touches. When he collapses in the snow, desperately clinging to life, he is rescued by Rikuou, who takes him back to Green Drugstore, a pharmacy dealing in more than just your everyday items.
Kazahaya finds himself working in the store, indebted to the owner, Kakei, for giving him a job and a place to lodge. Somehow, Kakei knows about Kazahaya's abilities, and soon he and Rikuou are sent on the occasional side job, involving the use of their unique talents.
As the story progresses, more is revealed about the mysterious pasts of the two main characters. Why did Kazahaya end up collapsed in the snow? Who is the mysterious girl that Kazahaya keeps seeing in Rikuou's mind, and what exactly happened to her?

Watanuki Kimihiro is haunted by visions of ghosts and spirits. Seemingly by chance, he encounters a mysterious witch named Y?ko, who claims she can help. In desperation, he accepts, but realizes that he's just been tricked into working for Y?ko in order to pay off the cost of her services. Soon he's employed in her little shop- a job which turns out to be nothing like his previous work experience!

Collection of short comedic Akagi parodies from a number of artists, including Washizu-sama to Yukai na Nakama-tachi by CLAMP that was used to advertise the release of Washizu -Enma no Touhai-.
3. Washizu-sama to Yukai na Nakama-tachi
A one-shot from the female art team CLAMP featuring Washizu Iwao from the gambling manga Akagi as part of a promotion for the new Washizu manga.

Hinata Asahi is a high school student who lives alone with only her teddy bears to keep her company. Her life becomes much more exciting when the handsome Shirou Asou, moves in next door -- not only is he really cute (even if much older), but he's also her new teacher! Hina has a bit of a crush on Asou-sensei, but when the older man seems to take an interest in her as well, is it a forbidden love or something else? (Source: Tokyopop)