I write on the straws, bottles, jars, etc. with a permanent marker. Works very well on the straws; more limited success on glass jars that go in the refrigerator (at home obviously). 'Permanent' marker has a tendency to rub off glass over time, especially if it gets wet (like from condensation). Writing where you won't be likely to hold the glass container helps.

Note: permanent marker can be cleaned off (or at least mostly off) plastic containers and lids with a scrubbie.

-FA