Most Oscar acceptance speeches come and go with seemingly little forethought and even less resonance. But a few speeches have had lasting impact - for better or worse.

"In some ways, your Oscar speech is as important as the movie performance that got you the award," says Tom O'Neil, author of "Movie Awards." "It's your chance to live forever in showbiz history. Or bore them to tears and come off as selfish and pampered."

USA Today has compiled the following list of do's and don't's for winners at tonight's ceremonies.

Have a memorable phrase.

Sally Field etched her place in history with her speech for 1984's "Places in the Heart" with "I can't deny the fact that you like me, right now, you like me!" Louise Fletcher won over the audience when, accepting her Oscar for playing the evil nurse in 1975's "One Flew Over the Cuckoo's Nest," she said, "I've loved being hated by you." "You want to make an impression," says film historian Leonard Maltin. "Being clever helps."

Shed some tears.

Halle Berry didn't leave many dry eyes in the house with her tearful acceptance speech for 2001's "Monster's Ball." "This moment is for Dorothy Dandridge, Lena Horne, Diahann Carroll," she bawled. "It's for the women that stand beside me - Jada Pinkett, Angela Bassett - and it's for every nameless, faceless woman of color that now has a chance because this door tonight has been opened."

Express yourself without words.

Great acceptance speeches aren't always about what's said. Few people saw 2002's "The Pianist," but who can forget Oscar winner Adrien Brody planting a kiss on presenter Berry? Or Jack Palance, having just won a supporting-actor award for 1991's "City Slickers," doing one-handed push-ups?

Keep it short.

Long-winded Oscar speeches are the death of ratings. Jane Wyman got it right when accepting her Oscar for playing a mute character in 1948's "Johnny Belinda": "I accept this very gratefully for keeping my mouth shut for once. I think I'll do it again." She then sat down.

Pull out a piece of paper.

If you see a sliver of white coming from a winner's pocket, "It's over," says Bruce Vilanch, a writer for this year's ceremony. "Once you see they've got a list, people have already stopped listening."

Jennifer Connelly's acceptance speech for her best-actress Oscar for 2001's "A Beautiful Mind" "was one of the worst I can remember, because she was just reading a speech," says Emanuel Levy, author of "All About Oscar." "It takes all the emotion out of it."

Get (too) political.

In 1973, Sacheen Littlefeather took the stage to decline Marlon Brando's best-actor Oscar for "The Godfather," then berated the United States for its treatment of Native Americans. The speech drew boos.

Of course, politics also can provide some colorful fireworks. Michael Moore, who won for 2002's "Bowling for Columbine," received a standing ovation and jeers for an anti-war speech that called President Bush a "fictitious president."

"I loved it," Vilanch recalls, "because we were busy backstage trying to write jokes for (host Steve Martin)." It worked. Martin came back with a quip that the Teamsters loved the speech and were "helping Mr. Moore into the trunk of his car."

Thank your agent.

Or lawyer. Or any other Hollywood types getting rich off your success. "It's one thing to thank your mother, or someone who helped get your first job so you didn't have to sleep in your car," O'Neil says. "Hilary Swank gave one of the best speeches (for 1999's "Boys Don't Cry") by staying personal. But who wants to hear a list of attorneys?"

Ultimately, "you just need to have an honest, spontaneous emotion on stage," Maltin says. "Something that shows people that you're happy you won."