With Star Trek: Nemesis set to hit theaters this year, Trekkies will likely be meeting at their famous conventions to discuss Capt. Picard's latest adventures.

But they aren't the only eccentric club members to gather at offbeat conferences. Fans of The Wizard of Oz, Alice in Wonderland, Sherlock Holmes, Nancy Drew and a host of other treasured characters and stories are holding lesser-known conventions around the country.

Not surprisingly, many of the groups have been established out of feelings of wistfulness for the past.

"It's childhood nostalgia," said Jenn Fisher, 29, president of the Nancy Drew Sleuths. "I read Nancy Drew as a child and loved it. [Club members] feel like she inspired them to do more in life. She was so independent and bold."

The wildly popular Nancy Drew series about the adventures of the teenage detective was so successful that it took numerous ghostwriters to produce the books, and new ones are still being published today. The club, which started as an online discussion group and still holds Internet chats, focuses on book collecting, swapping and analyzing.

"I enjoy bringing collectors together to talk about the books," said Fisher, of Adrian, Texas. She said the hokey plots are often a focal point of the discussions.

Reading and book collecting are also shared hobbies among members of the International Wizard of Oz Club, who discuss the 40-book series by L. Frank Baum and other writers. The much-celebrated 1939 film starring Judy Garland was based on the first book.

"It's our own American fairy tale," said club member Barbara Koelle, 78, of Swarthmore, Pa. "It's well-written. Many authors have said it influenced them."

While the Nancy Drew Sleuths is only two years old, the Oz Club has been around since the 1950s, said Koelle, who has served as both president and editor of the organization's publication The Baum Bugle.

"I went to the first convention in Indiana and I've never looked back," Koelle said. "The people are interesting, and they know a lot about the books."

In addition to collecting, reading and talking about the series, club members can attend one of the three summer conventions around the country. Those gatherings feature workshops, Oz paraphernalia auctions and speeches by guests. Several of the Munchkins as well as Margaret Hamilton, who played the Wicked Witch of the West in the film, have spoken at the conventions.

Koelle said some particularly adventurous members come to the conferences in costume. One man arrived dressed as a Book 2 character called Jack Pumpkinhead -- and wore an actual pumpkin on his head.

The appeal of the Oz stories, according to Koelle, is their otherworldliness.

"I like the fantasy part of it," she said. "[The characters] are realistic, even though they're dealing with magic."

Koelle's husband, Jack, belongs to yet another little-known group with its own obsession: Sherlock Holmes.

The Sons of the Copper Beeches is the Philadelphia chapter of the national Baker Street Irregulars -- as the Holmes society is called. The all-male local group holds dinner parties at which Sir Arthur Conan Doyle's famous stories and novels about the ever-logical private detective are discussed.

"We have nuts like myself who think this is really fun, and really intense characters who take this as the holy writ and all sorts of shades in between," said Mr. Koelle, 81.

Among the favorite topics of conversation, according to Mr. Koelle, are the irregularities one can find in the 56 short stories and four novels about Sherlock Holmes.

"Doyle was a very casual writer. He didn't bother to check his facts all that carefully," Mr. Koelle said. "There are a lot of inconsistencies and those inconsistencies that pop up make for stimulating conversations."

The national Holmes club, which is now co-ed but wasn't when it was founded in 1934, has between 500 and 600 members, he said.

Mr. Koelle said the appeal is not only nostalgia, but also the quality of the writing and the vividness of Doyle's characters.

"The characters seem alive -- it's hard to believe they didn't really live," said Mr. Koelle. "Doyle was a fine writer and these are very, very intriguing stories. They're fun to remember and exchange views about."