1. Quickly transitioning from a calm state of mind to an enormous freakout over technology not working or the discovery of something new that you know you don't really need but you have to have it.
2. The act of taking a serious moment and making yourself appear as a retarded/spazstic person to enable a conversation stopper.
Why is he over there nashing like crazy?
Oh, he just discovered he had a virus on his computer.
Do you want to go to bestbuy and nash on some new stuff?
Will you stop nashing and let me talk about the STD I just contacted?