To add clarity to this discussion, check this out...

10And the devil that
deceived them was cast into the lake of fire and brimstone, where the
beast and the false prophet are, and shall be tormented day and night
for ever and ever.

 11And
I saw a great white throne, and him that sat on it, from whose face the
earth and the heaven fled away; and there was found no place for them.

 12And
I saw the dead, small and great, stand before God; and the books were
opened: and another book was opened, which is the book of life: and the
dead were judged out of those things which were written in the books,
according to their works.

 13And
the sea gave up the dead which were in it; and death and hell delivered
up the dead which were in them: and they were judged every man
according to their works.

 14And death and hell were cast into the lake of fire. This is the second death.

 15And whosoever was not found written in the book of life was cast into the lake of fire.

Now, here's the question: is the "second death" everlasting for the unsaved, or is it the simply the end to their existence?