Tetris block sticky notes for the art director/designer who is also a geek (ie: ME! and yeah, loads of people like me). Ben Ambrose designed these little blocks of loverly, and you can fetch them for £7.50 at Suck.uk.com
Of course there is, and since it's over ten years old it can be legitimately classed as 'retro', which means it can automatically be classed as cool, which means we can feel justified in producing these cool, retro, block sticky notes. Where is more apt to note down reminders than elements of old video games rendered in pale yellow paper - evoking memories from your youth while jogging your memory to buy some milk and/or call your nan.