What do you call those terrarium-like things with grow lights in them for growing vegetables?
Yeah, vegetables, that’s it 
But seriously, I used to see those things advertised everywhere, and I haven’t lately. I’m trying to find one online, but I have no idea what they’re called. They were supposed to grow “vegetables” in record time.
Do any of you know what I’m talking about, and if so, are they worth the price?
It sounds like a greenhouse. A very small greenhouse is called a Cold Box. I don’t think they use grow lights. You probably want a hydroponic growing system.
I think you are talking about that thing they used to order from TV and they showed a ton of vegetables growing on a single stand on the dining table for fresh vegetables, spices and herbs, etc. No, they are not worth it.
If you want to grow, or start veggies indoors, I would get a real starter kit, see link.
If I remember correctly the ones you are talking about are Kia Pet or something, like that dog that grew grass hair, etc. Can’t remember the name.
You want a hydroponics set up and a closet in the house to put your system in. They work well.