Aw, man, I got so busy yesterday I forgot to actually post the answers to the trivia. So here it is. Sorry about that! Not that I really need to post them, since the commenters had all the right answers (collectively).
1. Who invented the first compiler?
Grace Hopper.
2. What optical phenomenon is the basis for fiber optics, and also is how most automotive rain sensors work?
Total internal reflection.
3. An early form of RAM was magnetic ceramic rings with wires threaded through them. What was the more common name for this memory?
Core memory (and hence the term “core dumps”).
4. What computer systems had the operating system called UNICOS?
Cray supercomputers.
5. What designation did Intel give 80486 CPUs with a defective floating point unit?
80486SX. The add-on FPU, the 80487, was actually just a full 80486DX CPU with a working FPU.