Speculative technologies in science fiction have long inspired advancements in Human-Computer Interaction (HCI). Doraemon, a Japanese manga featuring a robotic cat from the 22nd century, presents an extensive collection of futuristic gadgets-an underexplored source of speculative technologies. This study systematically analyses 379 of these gadgets, categorising them into 33 subcategories within 10 high-level groupings, to examine the fundamental human needs they address, their parallels to contemporary technologies, and their potential insights for HCI design. The findings reveal that while human needs remain constant, the ways in which technology fulfils them differ. Doraemon's gadgets emphasise tangible, single-purpose interactions with built-in reversibility, contrasting with the increasing complexity and software-driven nature of modern systems. By examining these speculative technologies, this study highlights alternative interaction paradigms that challenge current HCI trends and offer inspiration for future user-centred innovation.