plutonium

1.    .--------.       Visit  your  local junk yard and get a lead box or if you
      |========|       can't find one, use an old coffee can.
      |        |
      | ------ |       Obtain  107kg of weapons grade Plutonium. This is readily
      | Coffee |       available from the Russian Mafia.
      | ------ |       Wash your hands after handling and don't  allow  children
      |        |       or pets to eat it). Store the Plutonium in the can.
      |________|

2.      ______
   ____|[____]|____
  |                |
  |                |
  |                |   You'll need a metal enclosure to house the device.
  |                |   Any  common  variety  of  sheet metal can be bent to the
  |                |   desired shape as can  a  metal  briefcase but DO NOT use
  |                |   aluminium foil.
  |                |
  |                |
  |________________|

3.
       .-:##:-.
      /  |##|  \      Arrange the Plutonium in two hemisphere held 3cm apart by
     |   |##|   |     rubber cement.
      \  |##|  /
       `-:##:-'
4.
      _.-""""-._
    .'          `.
   /   .-:##:-.   \   Pack the outside of the Plutonium with a thick  layer  of
  |   /  |##|  \   |  gelignite.  If  you  can't get gelignite you can used TNT
  |  |   |##|   |  |  packed in Playdo or any modeling clay. It  is  acceptable
  |   \  |##|  /   |  to  use  coloured  clay  but there's no need for anything
   \   `-:##:-'   /   fancy.
    `._        _.'
       `-....-'
5.
        ______
   ____|[____]|____
  |   _.-""""-._   |
  | .'          `. |
  |/   .-:##:-.   \|
  |   /  |##|  \   |  Fix  the  structure to the inside of the metal case using
  |  |   |##|   |  |  strong glue such as SupaGlue or similar. This must  be  a
  |   \  |##|  /   |  firm bond to prevent accidental detonation resulting from
  |\   `-:##:-'   /|  vibration or mishandling.
  | `._        _.' |
  |____`-....-'____|