Remember that whole Mario 25th anniversary thing? Nintendo's not ready to let you forget. It's just launched a new official 25th anniversary website that challenges you to make Mario-themed flipnotes.
The retro-decorated site, full of sprites from Super Mario Bros. 1, asks DSi and DSi XL owners to use the DSiWare Flipnote Studio software to create their little animations, in combination with some sound effect samples it provides.
You need to send them in to Nintendo between now and November 19 - although it doesn't mention any form of prize for the best ones, so we presume it's just for fun and Nintendo will post your creations on the site.
Head through the source link below for full instructions.