ROUJIN Z is a classic feature length anime by director Katsuhiro Otomo the creator of AKIRA. Unlike AKIRA, ROUJIN Z is a comedy.
An experimental computerized sick bed malfunctions and goes on a rampage through Tokyo with an invalid old man aboard. (Roujin means old man in Japanese.) The out of control atomic powered bed adds other machines to itself and grows to gigantic proportions. (much like Tetsuo's out of control body in AKIRA.) There's plenty of action and laughs with teens in trouble, bumbling bureaucrats and giant fighting robots.
The 1998 DVD contains the original version subtitled, and a dubbed English version. Even if you don't like English dubs, watch this one for the extra jokes the scripter added to the film.