Sarcasm? I hope...
Calculators and velcro.
My kids were never allowed calculators during their homeschool career.
I never allowed footwear that didn't tie.
Between calculators, velcro and TV, I'd guess at least 50% of basic skills are not lost, but never learned, to the detriment of a child's (and ultimately adult's) ability to formulate thought processes (sp?) required to reach a conclusion quickly and easily.