Another great moment came in four words: "Mister Sir Henry Motherfucker". Too perfect.
During the trip across the beach to fight Holly Summers, Travis destroys multiple electric fences, and as he tries to walk over them, the game shows a cutsene where he steps on a land mine and gets blown a few feet away. After he destroys the last one, we see a cutsene where he almost puts his foot on a landmine, stops, smirks as if to say "not falling for that again" and steps over the mine... only to step right on another one. Cue Skyward Scream.
Just before said trip, there's the look on Travis' face as he's rubbing suntan lotion on Sylvia's leg.
In the cutscene before you fight Holly Summers, she throws three grenades into a pit with Travis inside it (complete with cartoonish whistling noises). Holly then casually waves as Travis is launched into the air with three explosions while he lets out a rather girly scream.
Admittedly the result of a Good Bad Bug on Bitter, one player had Travis pull off a wrestling move on a Mook during the Bad Girl boss fight. During this time, Travis had thrown his beam katana skyward. When Travis was then knocked out of this by Bad Girl using another Mook for her Fastball Special, he stood up without his katana. He was then able to beat Bad Girl with Travis apparently using nothing at all to charge beam attacks and slash her to pieces. Travis didn't get it back until the cutscene after. Guess Silvia wasn't kidding when she said to "Trust your Force!"
Some of Travis' problems with the Beef Head video store, from returning a video of someone, possibly Travis himself, getting it on with a pillow to a botched attempt at recording a naughty video and returning the copy to the store.
The death wails of the many Mooks Travis slaughters throughout his adventures, including "MY SPLEEN!", "MOMMA!" and "I'M STILL A VIRGIN!"
On your way to fight Shinobu, you'll encounter a mook who'll activate a sprinkler, causing the beam katana to short circuit and Travis to waddle around with the music sped up.
Travis trying to block Dr. Peace's bullet by hitting it out of Destroy Stadium like a baseball, though when the bullet makes contact with the beam katana, the force of the impact sends Travis flying a good 50 or so feet and crashes into the wall, Looney Tunes style.
The ENTIRETY of the fight with HarveyVolodarkski, mostly based on his OUTRAGEOUSAccent, and the fact he's so Affably Evil. Here's a gem of line in the prefight scene (right after he calls Travis to the stage as a "volunteer").
Harvey: Tell the audience your name!
Travis: Travis Touchdown. It's a good name, dont'cha think?
Harvey: It's a fine name indeed! You have your parents to thank for that!
If Travis escapes from the death trap during his duel with Harvey, the two immediately stop the fight to wave at the audience before resuming the duel.
Lose a weapons clash with Harvey and he will turn your beam katana into a magic wand that looks like it could be used by a protagonist in a Magical Girl show. Made funnier if Travis happens to be wearing his Bizarre Jelly outfit.