I heard once that you could send stuff (like Bday cards, letters, etc) to the Bong mags address.  Here they are:

Bong
PO Box 1281
London, N1
9UX, UK

-or-

Bong
PO Box 4596
Grand Central Station
New York, NY 10163 USA

You might spot Martin at Andy's restaurtant:

Gascogne
12 Blenheim Terrace
London NW8