has he appeared on screen ever?
"The Blues Brothers", "Gremlins", "Vanilla Sky", and "Goldmember".
Steven Spielberg
Spielberg had cameo roles in "The Blues Brothers", "Gremlins", "Vanilla Sky", and "Austin Powers in Goldmember", as well as small uncredited cameos in a handful of other films, such as a life-station worker in "Jaws". 
what breed of horse is joey in war horse Thoroughbred horse when was the film released? 2011 who produced it? Steven Spielberg where was it filmed? Dartmoor, Devon when was it premiered? December 25, 2011 was it nominated for any award? It was nominated for six Academy Awards, two Golden Globe Awards and five BAFTAs. what does the last one stand for? It honours the best national and foreign films. where is the producer from? Cincinnati, Ohio. which projects will he be doing in the future? UNANSWERABLE where did he spend his childhood? Phoenix, Arizona.
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Steven Spielberg [SEP] Onscreen appearances
Spielberg had cameo roles in "The Blues Brothers", "Gremlins", "Vanilla Sky", and "Austin Powers in Goldmember", as well as small uncredited cameos in a handful of other films, such as a life-station worker in "Jaws". He also made numerous cameo roles in the Warner Bros. cartoons he produced, such as Animaniacs, and even made reference to some of his films. Spielberg voiced himself in the film "Paul", and in one episode of "Tiny Toon Adventures" titled "Buster and Babs Go Hawaiian". In 2017, Spielberg, along with fellow directors Francis Ford Coppola, Guillermo del Toro, Paul Greengrass and Lawrence Kasdan were featured in the Netflix documentary series "Five Came Back", which discussed the contributions of film directors Frank Capra, John Ford, John Huston, George Stevens and William Wyler towards recording the events of World War II.