On running top, it is gnome-terminal that is on the increase. Memory
usage for this process has gone from 7% to 17.7% in the time taken to
write this email. I have to keep killing my gnome-terminal so turning
off my poor machine.
That's odd. I don't use Gnome, but I thought gnome-terminal was just
shell terminal like xterm or kterm. As such it doesn't do anything on
its own and killing shouldn't turn off your machine. Are you sure it
isn't something running from the gnome-terminal that is using up all the
memory?