Twang-a-what?

What the heck is a twanginator?
My Mom emails me and tells me that my Dad bought one.
I figured out from the email that it's some sort of musical instrument. But a search on Google produced mixed results, and no real picture or definition. From what I did gather, it's some sort of guitar thing.
Probably has a real name, but some old hippie called it a "twanginator" and now it's known by that term too. 
Probably "twangs" too.
I guess I'll find out on the weekend, when I may get a chance to see it.