Brown Marmorated Stink Bug eggs! Thanks, Mojave- mystery solved. Too late to hatch to be sure as they went down the toilet with the next flush.
Can't tell you how many of these things I killed last year and how many we've found stashed away in the garden shed in every conceivable spot.
I haven't seen them out and about in the garden yet, so it's kind of surprising to find these eggs already. I'll definitely keep my eye out for more, though.