NEW YORK — If they gave out Oscars for self-parody, Neil Patrick Harris would be writing his acceptance speech.

The former child star mocks himself — and then some — in the comedy "Harold & Kumar Escape From Guantanamo Bay." To the delight of fans and critics alike, he reprises his turn as Neil Patrick Harris, a doped-up, egomaniacal, prostitute-loving, unicorn-riding narcissist wielding his own personalized branding iron.

"Actors are known for being emotional, ego-based individuals. But I think it's important to not take oneself too seriously," says Harris, 34.

He did have some standards when shooting the comedy's fantasy equine scene: "They had (me) wearing a really crazy tie-dye sleeveless vest with fur on it. I said if I have to dress like a crazy man on top of a unicorn, I just think I'll never hear the end of it. So I got to dress normally on top of a unicorn, to save face."

Harris says he's open to doing a third installment of "Harold & Kumar," and to those who see the film and wonder how he could possibly return, just watch the credits for a hint.

For now, though, Harris is busy with his day job, playing womanizing party boy Barney in the CBS sitcom "How I Met Your Mother" (Mondays, 7:30 p.m.); Britney Spears famously guest-starred on the show, and the word is she's coming back.

"We were so conscious when she arrived to treat her well but not ridiculously special," Harris says. "We wanted her to feel like a guest on our show. We wanted her to feel comfortable so she could do the work. And she did."

As for Barney, "there's a nice dramatic wrinkle that will happen for (him) for the last few episodes. I would be remiss to reveal what that is, but the ramifications last for more than one episode."

In reality, Harris has little in common with either social butterfly Barney or his overblown movie persona, aside from the characters' quick wit. "Harold & Kumar" co-writer/co-director Jon Hurwitz calls Harris "the life of the party. The character of Neil Patrick Harris does a lot of bad things, and is an arrogant jerk, but is kind of cool and talky. In real life, he's a much more humble guy. He's got the quickest wit. You can say anything and he always has a quick one-liner.

He has been in a relationship with actor David Burtka for four years, something he never tried to hide, even before 2006, when he first publicly discussed being gay.

"The impact was minimal, and that in turn had great impact on me. I was pleased about society's indifference about it," Harris says. "My story is so personal to me that I didn't really feel like it was a great announcement that required any kudos or disdain, and, in turn, I got neither."

Harris and Burtka — along with their two dogs — are bicoastal. They'd like to have children some day, "but seeing as we're both actor gypsy people right now, we're not settled enough to commit to 18 years," Harris says. Eventually, he says, they'll be back in New York full time, where they own a place uptown. "At the end of the day, I'll end up here. L.A. is a nice side trip."

Harris spends most of his evenings hosting game nights at their home, playing Heart's "Barracuda" on Guitar Hero or performing magic tricks.

"The last strip club I went to was probably seven or eight years ago. I did my partying when I was 22, 23, 24."

And younger. "I had a fake ID — it was all the rage back in the day — so I could go into clubs in L.A. and drink underage," Harris says. "I feel like 'going out' is trying to maintain fame. But it's a roundabout way to get it. If you work hard and work well, fame begets you — it will find you."

As a teen, he was a medical whiz in "Doogie Howser, M.D.," and after the show wrapped in 1993, Harris worked in TV ("Will & Grace"," Ed"), movies ("Starship Troopers," "Undercover Brother") and theater, starring in "Cabaret" and "Assassins" on Broadway. Now, he seems to have found his footing.

"You have to have patience in this business," he says. "That seems to be the big moral of my story. You can't take any step and assume it will lead to another step. You have to appreciate the step you're on."