Robz8 has posted a new video player for the Nintendo DS:

After 9 years (as of this post) since the latest version of MoonShell released, the SD-compatible alternative to MoonShell is finally here!
Introducing the Rocket Video Player! It's the video player that plays video files with an extension called ".rvid", bringing you the ultimate in picture quality, thanks to it's lossless frame data.
If the video is uncompressed, you may need a big enough SD card.


The same, but improved Rocket Video technology from TWiLight Menu++!
Console-based file browser to search for your .rvid file.
The video UI from the "DSi + Internet" app.
Support for videos up to 60FPS! (25-60FPS video requires the DS Memory Expansion Pak, or a DSi or 3DS with the app on the SD card.)
.rvid size for those FPS is limited to 11MB (DSi) or 16MB (DSi) (not counting header and sound data, so if it has sound, it may still play).
Both progressive and interlaced video.
Audio up to 16khz. (If you we're expecting higher, sorry, it's the best the sound could get without slowing things down too much.)

Video UI Controls (touching works too!)

A: Play/Pause
B: Exit video
Left: Jump back to beginning