Most interesting is ''Thumbtanic,'' acted with thumbs and due to wrap filming this Christmas

Just when you thought it was safe to go back on the cruise ship, along comes Titanic — the spoofs. No less than three takeoffs on the biggest box office boat of all time are getting the thumbs-up; and in one case, many thumbs up.

Titanic Too: It Missed the Iceberg stars parody paragons Leslie Nielsen and Priscilla Presley, whose sorry-ass ship bypasses the iceberg only to ram into other hazards. The $25 million project is written and directed by Naked Gun and Hot Shots! writer Pat Proft.

Gigantic tells the tale of Titanic‘s slightly shorter (by two inches) sister ship, which gets no publicity when it bashes into a wimpy coral reef on its maiden voyage. Mike Bender, 22, and his brother Chris, 27, wrote the film for New Line.

Hands down, though, the weirdest and most buzzed-about Titanic spoof is Thumbtanic, from director Steve Oedekerk (Ace Ventura: When Nature Calls). Set to wrap by year’s end, the 22 1/2-minute film (most likely direct-to-video) re-creates the nautical disaster with a cast of human thumbs. Oedekerk’s thumb plays a Leonardo DiCaprio-like role. The other thumbs are unknowns, but the director still hands it to them. ”The performances are incredible! The effects, you won’t believe!” Oedekerk insists. ”The thumbs’ faces look just like real faces.”

Yeah, but those fingers will have to be triple-jointed if any of the Titanic spoofs are going to float. This summer’s gag-fests Mafia! (a Godfather send-up) and Wrongfully Accused (a Fugitive spoof) were laughed out of theaters, earning $19.9 million and $9.6 million, respectively. Oedekerk thinks spoofs work if you ”offer the public something they haven’t seen before.” Producer Hal Liberman, who’s making the mockumentary New Jersey Turnpikes, agrees, adding that each parody should be judged ”on a case-by-case basis. After seeing what happened this summer, the public seems to be saying, I’ve had my fill of parodies.” Looks like our idea for [pi]tanic, about a ship of doomed math wizards, is dead in the water.