How to protect my Ubuntu PC in a non-secure wifi NW?

[Matthew Flaschen]

Peter Garrett wrote:
> For instance, I can check my mail from a cafe by connecting through my home computer via ssh, either using 
> gui apps like sylpheed or evolution, firefox etc, or from the commandline. The data is encrypted end-to-end.

How does this add security?  Presumably, you're connecting from your
home computer to the mailbox via a secure protocol.  So why not just
connect directly?  This should be secure even over unsecured wireless.

Matt Flaschen