@Lash,
Oooh, I love short-short stories!
That was pretty much my favorite thing as an English major.
Well, the stories I liked best were 2-3 pages. 100 words is super-short. I love it as an exercise.
Hard to say how I'd start. Probably just cast generally around for something vivid -- something that either carries a lot of punch right there or can suggest a lot more through power of allusion.
When I think of YOU writing a short-short story, I think of some sort of dialogue between some vivid characters with distinctive voices (older women maybe, though I'm not saying just re-do your funeral story), where there is something self-contained there but there are also hints at a vast backstory.