I needed something that only used ingredients I had on hand - no fancy onions or extra vegetables, no specialty vinegars or sauces.
Here's what I came up with, based on a few different recipes I found:
1 English cucumber, sliced thinly
4 tsp white vinegar
1/4 tsp white sugar
1/8 tsp salt
Mix vinegar, sugar, and salt - I found it helped to toss it in the microwave for 5 to 10 seconds to help everything dissolve.
Pour over sliced cucumbers. Toss.
Drain excess liquid, so the cukes don't get soggy.
It's the perfect combination of sweet, salty, tart, and crunchy. A nice light addition to many lunches and dinners in the last week or two.