- Neil is 6′ 1½” (1.87 m) tall.
- Both of his parents are lawyers, and they now own a restaurant called Perreniel’s in Albuquerue. He has a brother, Brian, born in 1970.
- His favourite movie is Hitchcock’s Rear Window.
- It was by following his brother to an audition in fourth grade that he first began acting – as Toto in a school production of The Wizard of Oz.
- Went to the same high school as Freddie Prinze Jr (La Cueva High School in Albuquerque). Neil graduated with honors in 1991.
- Neil was Terri Colombino’s date to her senior prom.
- Has sung since he was a child. His father played the folk guitar and together they entertained.
- Neil’s performance in the stage version of Rent garnered him a Drama-League Award in 1997.
- Is an avid Les Miserables fan, and performed the song “The Confrontation” with his co-star Jason Segel (both of “How I Met Your Mother”) live on the Megan Mullally show. He performed the role of Javert, to wild cheers from the audience.
- Recorded a RiffTrax commentary for Willy Wonka & The Chocolate Factory.
- Notable roles he missed out on: Nightcrawler in the movie X2: X-Men United (which went to Alan Cumming) and Simon Tam in the Joss Whedon series Firefly (which went to Sean Maher).
- In 2005, was named the Best Return to Television by TV Guide Magazine, and Sexiest Comeback by People Magazine for his role as Barney in How I Met Your Mother. He was also chosen as one of People Magazine’s Sexiest Men Alive for 2007.
- Was the “Not My Job” guest on the April 5, 2008, episode of the National Public Radio quiz show “Wait Wait… Don’t Tell Me!”.
- He is an amateur magician. He has performed magic tricks on Letterman, Jay Leno, Ellen, as well as in character as Barney in How I Met Your Mother. In April 2008 he was voted onto the board of directors at Hollywood’s illustrious Magic Castle. He’s the first celebrity on the board since Cary Grant.
- In August 2008 he directed a magic show for the Edinburgh Fringe Festival, Guy Hollingworth’s The Expert at the Card Table.