Hamburger's live act, which is quite different from his many albums, features a barrage of question/answer jokes aimed often at celebrity targets as well as barbs aimed at his ex-wife. He has performed in front of audiences worldwide from Madison Square Garden to Jimmy Kimmel Live! and the confrontational aspects of his act have drawn comparisons to Tony Clifton. One of his most famous gags is the "Zipper Lips", in which he asks an audience member a question. If the audience member doesn't respond, Hamburger derides them for being a "zipper lips". A common phrase used by the comedian is "But that's my life!", which he uses when he mentions being humiliated or degraded for some reason.
Hamburger is a frequent guest on the internet talk show Tom Green's House Tonight. In 2006, Hamburger started doing his own show called Poolside Chats with Neil Hamburger on The Channel at Tomgreen.com. Guests on his show have included Tim and Eric, Kyle Gass of Tenacious D, Buzz Osborne of The Melvins, and Bonnie 'Prince' Billy.
In 2007, Hamburger opened for Tenacious D during their Pick of Destiny Tour. In the movie The Pick of Destiny, he made a brief cameo appearance before Tenacious D came on stage to perform. He has already performed at Madison Square Garden, a show that the New York Times referred to as likely "the greatest night of his career." However, his performance was poorly received elsewhere, with booing and heckling ensuing in countries such as Ireland and England. Critics say this was as a result of the crowd being eager to see Sam O'Donovan, who was originally booked but cancelled.
The Australian punk band Frenzal Rhomb have used Hamburger to open their sets and appear in their video clips for their songs "Punisher" and "Ballchef", and Frenzal Rhomb members Jay and the Doctor have called him live on air on their radio show on the network Triple J to report on current events in America such as award ceremonies.
In 2007, Hamburger appeared in the music video for "Conspiracy of the Gods" by the band Trans Am.
In September 2007 and 2010, he appeared at the Global ComedyFest in Vancouver, Canada. In 2010, he appeared at Just For Laughs in Montreal, and later that summer, at the Edinburgh Festival Fringe resulting in rave reviews in The Scotsman and The Guardian.
In spring of 2008, Drag City released an album of country and western originals and covers recorded by Neil Hamburger in a "celebrity vocals" style. During the sessions, Hamburger was backed by musicians including Prairie Prince of The Tubes and Todd Rundgren's band, David Gleason, Atom Ellis of Dieselhed and The New Cars, Rachel Haden from that dog.