Free homebrew multimedia-related applications for the Nintendo DS platform. You will find audio players of various forms (sequence/tracker stuff included), music creation tools (timing, tuning and such), painting tools, bookreaders (including PDF) and a handful of video players (including Moonshell).
Ah, yes, portrait mode, surely the best way to film a row of people. If only there were some way to fit a wider shot, at the expense of height... if only...