Fender have never made a production model doubleneck guitar (yes, there have been Custom Shop doublenecks), but that never stopped some of the Japanese manufacturers from the 1970s from having a go at combining two Fender designs into one.
Here we see an Ibanez Jazz Bass/Strat doubleneck, which could never be mistaken for a real Fender (if there was such a model to compare it to), but looks to be a very nicely made guitar. It's a nice touch having the two output jacks as you probably wouldn't want to put the separate halves of this guitar into the same amp.
It does look quite bulky though. I hate to think how much this would weigh and how backbreaking it would be.
It's probably one for the Ibanez collectors.