Well being a layman, I had no idea if I was joking or not. :)

Actually the idea of negative mass made me wonder if this would open the possibility for FTL space travel...Ran into a comment on the internets somewhere that said "no, because the mass is squared in the relation with energy, but the existence of imaginary masses might"

Thanks for the link.

Many times people will see an asymptote and say "Hey, what would happen if I crossed that? What would the math and physics look like?"

Tachyons are actually a great example of this. Taking the relativistic mass equation and asking "What would happen if I allowed for speeds larger than the speed of light?" Science is more a process of elimination. What does the math say? Can we observe what the math says should happen? Repeat.