Doesn’t have to be a thing you bought. Just some thing you didn’t have but then once you did it expanded your scope of actions.
The first obvious example that comes to mind is a car. Plenty of drawbacks to prevalence of cars, but being able to go where I want when I want, and far away, is very transformative.
I’m interested in other examples of things that aren’t just useful, but that open new possibilities.
Literally, tyrosine and iodine, because my thyroid gland was running slow and I was feeling cold most of the year. Now my body’s idling power is higher.