On the side he's also a musician, playing a mixture of indie, folk and psychedelic rock in the band Grape Digging Sharon Fruits, playing harder, Post-Rock-ish material as I'm the Manager, or releasing electronic and lo-fi solo material under the handles Locust Toybox and Stegosaurus Trap respectively. Firth also directed the music video for Flying Lotus' single "Ready Err Not," which premiered on Adult Swim in Halloween 2014.
- Black And White Cartoon
- Burnt Face Man
- Hell (a Stop Motion collaboration with two other animators)
- Jerry Jackson
- Not Stanley
- Salad Fingers
- Spoilsbury Toast Boy
- The World Within a Sock
- The News Hasn't Happened Yet
- Black Comedy
- Corrupt Corporate Executive: The entire twist of Cream is that a group of these ruined everything for everybody. The titular Cream is so helpful and rejuvenating that nearly all problems, including bodily defects, world hunger, poverty, deforestation, and running out of Cream itself, have been cured with no ill effects. However, because this made billionaires obsolete, the rich gathered up to create a campaign denouncing Cream and played into every vulnerability imaginable to get the public to swear off of it altogether. After things went back to normal, they redressed a perfectly normal cream as its healthier successor product and sold it to make more money.
- Crapsack World: The world of Salad Fingers and Spoilsbury Toast Boy is dark, bleak and hopeless.
- Limited Animation: Notable during his early days when using Flash. This began to disappear over time, espcially when Firth began using After Effects.
- No Indoor Voice: In Not Stanley.
- Oop North: Firth was born in Doncaster and currently based in Leeds.
- Promoted Fanboy: Firth is a fan of Warp Records artists like Aphex Twin, Boards of Canada and, most notably, Flying Lotus. He has, through the reputation he garnered for himself via Salad Fingers, ended up collabing with FlyLo several times and even has a writing credit on Flying Lotus's film "Kuso".
- Silly Walk: The main character in Not Stanley walks rather weirdly.
- Simple-Minded Wisdom: Not Stanley tends to veer between "Nonsequitor stand up" and "reflections on the world and society" within the same sentence.
- Surreal Humor / Surreal Horror: His body of work fluxes wildly between the two.
- Take That!: In his "Music Guess 2009" short, David Firth takes a stab at the music industry and the Lowest Common Denominator they're aiming for.
- Toilet Humor: The short "The Men From Up The Stairs" is a surreal, slightly satirical take on this.