time confetti
n. Brief scraps of leisure time scattered throughout a person‘s day.
Examples
2014
I wrote a few paragraphs of this column between school drop-off and an appointment. I sent a bunch of emails between making dinner and taekwondo. Bedtime reading with the kids, then more writing at 1 a.m., after a few hours of sleep. Then back up at 4 a.m. to write and sign up for summer camp.

There's a name for this. It's called "time confetti."
—Petula Dvorak, “Welcome to the land of Overwhelmia,” The Sydney Morning Herald, March 17, 2014
2014
What are the most frequent contributors to your time confetti? If you could convert all of your confetti into leisure time, would you feel guilty?
—“Reading Group Guide: Overwhelmed,” Book Keeping, January 31, 2014
2010 (earliest)
Fairly quickly, I discovered that my anxiety is fueled by the fact that I do very little in chunks of concentrated time. Instead, my days are chopped up like little bits of time confetti.
—Brigid Schulte, “The Test of Time,” The Washington Post, January 17, 2010