How to be a top selling author!

No idea.
More to the point, I’m don’t think I’d want to be a top sell­ing author. The qual­i­ty of writ­ing is rear­ly pro­por­tion­al to the com­er­cial sucess.
How­ev­er from time to time I do write (and I like to think that some of it isn’t crap). But what to write? When? First an idea is need­ed.
I have some tools and tech­niques that I use to cre­ate the spark, noth­ing all that inter­est­ing, but usu­al­ly works when I’m stuck for an idea.
Once I have an idea I look at all the pos­si­ble sto­ries I could tell with that and I start down the path that seems both inter­est­ing and chal­lang­ing to me. But giv­en the same spark anoth­er writer would nev­er write the same thing.
So with that in mind here is the brief:
Write a short (very short) sto­ry (or what­ev­er, peom, pro­gram code, pray) with­in these lim­i­ta­tions, 250 words max­i­mum, must include the word “cubic”, must have 2 char­ac­ter (no more, no less), and if you spend more than an hour on it you’ve tak­en too long.