Seeking help: GURPSifying some odd ideas

[DataPacRat]

It's been a while since I skimmed over my full set of Powers, Power-Ups, and other character-building books, so I'd appreciate some guidance about which mechanics I should use for these various ideas.

The setting is a small-moon-sized space station, and is technically hard-SF with no magic but a lot of bio-engineering; valid ways to accomplish various effects might be having everyone's brains to have been designed to work a certain way, or for custom species to have been built. The general goal is to have a surface appearance of a magical Sugarbowl setting, but for actual, discoverable mechanisms to underlie the seeming magic (bonus points for mechanisms that are disturbing or squicky) which can be exploited in new and interesting ways. I know that I can handwave all of this, but the more hard-numbered GURPS rules I can apply to any of these seemingly light-and-fluffy ideas (and which provide plot-useful limits), the better. (One reason I'd like hard numbers: for when characters from this setting start interacting with characters from outside it, with much mutual bogglement.)


* Consensual Guided Hallucinations. A character who can interact with others in such a way that outsiders would see them playing in an attic or the like, but by the end of it the participants would remember having lived through whatever interactive story was spun, meeting whatever characters were described, and so on. No harm worse than a mild scare possible, no locking people into un-reality. May seem to last as long as any story lasts, but doesn't really last longer than an afternoon. (It would be nice if the mechanisms of the light-and-fluffy version could eventually be adapted to more comprehensive forms of mind control.)

- Related to the above, items with similar effects, such as a kiddie pool in which full-fledged piratical adventures can seem to be had, or a full-sized pool that seems to be filled with whatever the swimmers want it to be, or play-rooms in which play-time seems to last several times longer than it really does, or doodle-chalk that seems to create animated 'chalk creatures', or a school bus leading to ridiculous field trips, or "portals" to chalk-drawing worlds or candy worlds or Lego worlds, and so on.

- Imaginary friend. Probably related to the above, a seemingly-independent character which only one person can see, unless other people squint really hard. Possibly related to present-day "tulpas".


* Spontaneous Musicalism. If one person starts singing, most other characters in earshot will be able to at least move to the beat, and if they want, can instinctively join in as backup singers or as part of a dance number. (Maybe built as Racial Skills, explained via very-carefully genetically-engineered brain structures?)


* Invisible Fairies. Under ordinary circumstances, various objects have interesting and useful effects tied to them, for which no obvious mechanism is visible; but which turn out to be taken care of by small creatures and/or people with colour-changing skin/fur/whatever and high Stealth scores. A hamper, which clothes tossed into get automatically washed and repaired by morning. A small bookshelf regularly restocked with whatever light reading its owner would most likely find enjoyable that day. A backpack that, every morning, is loaded with a dozen peanut butter sandwiches or unlimited string cheese. A toy box filled with unlimited Lego, or a bucket of unlimited water balloons.

- Toys that seem to be "powered by the imagination", but are really being moved around by said fairies.

- "Magic spells" which call on various subspecies of the fairies to perform various specific tasks.


* Once the basic approaches are down pat, then if possible, I'd like to figure out how to use more refined variations. Say, coming up with the closest that can be built to a Green Lantern Ring, without using any super-science or magic. "Hard light" wouldn't work as an explanation - but discreetly keeping a cache of super-Lego and invisible fairies nearby but out of sight, ready to respond to commands spoken into a ring-shaped microphone/radio, just might.


* Anyone have any suggestions for stats for swarms of small snake-like critters, which can replace a plush toy's stuffing, form a little hivemind, and animate it?