The Didj was LeapFrog's custom learning handheld, released in 2008 as a step up from the Leapster for older children, with games tied to school subjects like maths, spelling and reading. The startup sound played during the brief splash screen as the system booted, so every owner heard it each time they switched the device on. As the Didj faded from shops, its chime survived in retro tech videos, nostalgia posts and soundboard collections, where it is now used less as a boot sound and more as a shorthand for 2000s kids electronics.