Assorted Mystery Connectors

Assortment of mystery connectors. Everything shown in the first photo is included. These are junk, no matter how you look at them. What on earth are they for?

Black and green items shown in photos 2-3:
2 connectors for connecting USB mice or keyboards to PS/2 ports.
The black one is ELECOM brand, and the green one is Microsoft brand. They are likely not universally compatible and were probably intended for specific products. I vaguely recall them being included with mice.

Off-white items shown in photos 2-4:
1 SCSI terminator (estimated).

This is all I can identify. Regarding the rest, their origin, purpose, and identity are completely unknown (I've summarized them in a style reminiscent of Snatcher), but I've noted a few observations below.

The items shown in photo 8 appear to be identical to another similar item, likely the same product. Perhaps they are some kind of assembly-type terminal where a cable is inserted and then assembled?

The silver items shown in photos 9 onwards all seem like they could connect to TV antenna cables, and I suspect they are for some kind of relay or distribution, but I haven't tested them, so I can't say for sure. There are two T-shaped items that appear to be identical, and two T-shaped items with a thicker base that also appear identical. In addition, there is one item that looks like a straight connector, for a total of five items.