Has the world's greatest invention already been invented?

Well, i'd have to say that's kind of a paradox. Of course for us it's been invented, because who knows what someone will invent two days from now, or 50 years from now. It's mind boggling what some people can come up with, and amazing. I'd have to say though, beyond of course the wheel, and fire. The piece of technology that affects my life every day is my computer. I'm able to communicate to my family and friends faster, i'm able to send photo's that we've taken two seconds before, to buy gifts online, and to work online. Now, it's not completely my life, but it's nice to be able to keep in daily touch with people you're close to, hundreds or even thousands of miles away. Plus there's just so many things we do, day to day, that we take advantage of, that are amazing. Plastic, glass, ovens. Fridge's. LOL

The discovery of pencillan would have be the worlds greatest invention. It has saved countless lives and untold suffering & misery.