Obviously this wouldn't be compatible with current DS or 3DS games, but something like this will probably be the next gen Nintendo system. I'm talking about the first and third option; playing with it on the go or hooking it up to the tv. The thing with the phone won't happen, and I don't really see how it would be practical. With Nintendo merging their two hardware divisions, the next console will probably be both a (very powerful) handheld as well as a full fledged home-console.

That would be brilliant actually. Able to use (3D)TV or a smartphone as the second screen or play without when it isn't (really) needed? That's better than an actual 3DS!

And at $99 I'd be sure to pick it up too.

LOL. Why does this have to be a joke? Now I want one!

While it's only a joke, I can see this not happening though as it'll make the Wii U less relevant than it already is. The Wii U, although more powerful, is nothing more than a consolized version of the DS.  So what happens when people say, "why buy the Wii U when the 1DS can do the same thing with games from the DS and the 3DS?"