After spending a bunch of time thinking about illithid worlds due to Spelljammer, some general thoughts about things they will have lying around beyond the usual, recognisable stuff.
First, the general aesthetic will be:
- upsettingly asymmetrical because they like to hold things with their tentacles and long-fingered hands and like to know which way is the 'front' by feel
- flanged or ridged design with bits sticking out for ease of tentacle holding
- sensory tools for the senses of a mindflayer - emotion (empath), thought (telepathy), telekinesis, dream (which for them is 'channel the far realm'), body-mastery (a slightly taboo hobby of attuning with whatever form your tadpole took over)
- textural approach - etched in qualith text is very common both as instruction on the item, makers marks, dedications and other notes associated with its use or origin
- materials can include mother-of-pearl and other shell-like substances shaped into desired forms and highly precise carvings rendered using telekinetic abilities
d20 illithid cultural artifacts
1. Qualith meditation beads - quadripartite inscriptions spiralling around beads on a string, a relatively common design with a huge variety of writings available. Can be inscribed with koan-type truths, community doctrines, great questions, forget-me-not messages
2. Infinite sagas - a long flexible spiral, typically an embroidered or otherwise textured ribbon, containing stories that run on forever, reflecting the time-skipping nature of mindflayer dominion itself ".. until once more, at the far end of time, our Empire rose again and..."
3. Empathy detector - equivalent to an ear-horn, particularly for illithids who have spent too much time alone and want a little more clarity. Weakens defenses against 'blast' psychic attacks. Usually a hidden necklace as wearing one is a sign of weakness.
4. Emotional broadcaster - usually a very ostentatious head-piece that makes sure that what you feel, everyone else feels too. Wearing one of these is an illithid boss-move, be very sure of your place on the social ladder.
5. Empathy shield - for when others tiresome emotions are just not worth dealing with. Also provides some limited defense against psychic attacks. Usually a discrete brooch or pendant worn hidden as openly displaying you have one of these is seen as rude.