I just bought a multi-outlet pigtail adapter the other week and thought “Dang, I should have waited”, but it turns out, as long as you don’t mind blue, one of these is only $8 w/ free shipping ($16 for 2, $1 cheaper than Woot!, $6 if you factor in shipping). Plus it’s heavier duty being 12/3 gauge vs 14/3 (same amperage rating, though).
That is only free shipping if you are a prime member… shipping will be more than what Woot offers for your entire order, unless you add another $20 of eligible product to those extension cords.