which ground is best if you can't use RF?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>" <Beans45601-at-aol-dot-com>

Hello, i will be running my coil at school (lots) and the room where i will 
be running it in is far away from the outside. Which would be better. Using 
the ground plug in the wall, using cold water pipes (plenty of those), or 
running a 75' cable (or longer) outside.
Thanks
Adam
P.S. Aol has reccently decided to deliver my tesla mails, how come it is 
working now?