You wrote: 

There are other ways. Such as intantenous transfer. It wouldn't 
violate Relativity because speed is not involved.

If I understand Relativity correctly (and I'm not at all sure that I 
do), whether or not speed is involved doesn't matter.  *Information* 
cannot be transmitted faster than the speed of light.

Someone demonstrated to me once how any FTL information transfer makes 
possible causality violations.  If I remember right, it has something 
to do with two individuals, both in an inertial state, but traveling at 
a high percentage of c with respect to each other.  Both individuals 
would perceive the other's time as moving more slowly than their own.  
This is impossible, but it all works out, unless you have a method of 
FTL communication.  Then you have a situation where one individual can 
send a message to the other and receive a reply before he sent it.

Now, if you're willing to accept that causality violations aren't 
absurd (maybe they aren't), then FTL travel could be possible.

------RM