Lunar Train: old post I deleted, basically equatorial moon-encircling track(s) on which run Earth, Sun and Star Sidereal Trains for various purposes.

Tangential Space Landing: spherical'ish astronomical bodies of a particular size can be landed on / taken off from, tangentially instead of radially. Involves regenerative linear motors and spaceships with wheels on them :)

Nautilean Harp: Spiral backbone three-octave harp with 12 radii. Since each string is attached to its own other-octave strings through the spiral box structure you get seriously good resonance. Another version has the bass-strings in the middle all connected to a central point: this would have even greater resonance.

Googlechip: dedicated binary tree hardware: consists of cells each of which has 1 root and 2 branches. Each cell contains a transport node and a data node. The transport node processor deals with moving data around the bintree and is the part that's connected to the other cells. The data node processor and storage deals with it's data.

Rubik's Cubicle: ...

YouTuber: potates, eyes...

Internet Economy: requires domains to set prices for bytes recieved/transmitted. Thought it up a few years ago and actually had it working but I can't remember a key element or two :(

ExoRadial: transverse mounted cylinder with two pistons built inside a cam.

Religious Joke Exchange: somewhere I can spout "Jewish Ninja Throwing Stars of David" and "Buddha Bong" without worrying about earning a "racist" moniker.

Lawn Bidet: setting for a sprinkler

Pushups on a Cougar: ...