Mikey, what's in bottles tends to come from springs etc., what comes out of the tap has been - er - processed - so yes, there is stuff in it but only traces. Some water tastes gross, the worst I ever had was in Norfolk, you couldn't drink it out of the tap. Birmingham water comes from Wales, that was lovely and soft - down here in Kent it's really hard, it doesn't suit everyone. However, I wouldn't buy bottled unless I really needed it.
Sqad - LOL - yes, one gets on the train with ones coffee and one's i-Pad, it is quite a statement....