The following examples are 'thought provoking':

Dormitory......................Dirty Room
Evangelist.....................Evil's Agent
Desperation....................A Rope Ends It
The Morse Code.................Here Come Dots
Slot Machines..................Cash Lost in 'em
Animosity......................Is No Amity
Mother-in-law..................Woman Hitler
Snooze Alarms..................Alas! No More Z's
Alec Guinness..................Genuine Class
Semolina.......................Is No Meal
The Public Art Galleries.......Large Picture Halls, I Bet
A Decimal Point................I'm a Dot in Place
The Earthquakes................That Queer Shake
Eleven plus two................Twelve plus one
Contradiction..................Accord not in it

If you are familiar with the Evian brand of bottled water you can
spell it backwards to see what they think:

Evian..........................Naive

This one's amazing: (From Shakespeare's Hamlet)

"To be or not to be: that is the question,
whether tis nobler in the mind to suffer the slings
and arrows of outrageous fortune."

becomes:

"In one of the Bard's best-thought-of tragedies,
our insistent hero, Hamlet, queries on two fronts
about how life turns rotten."

And now, for some politicians:

George Herbert Walker Bush.....Huge Berserk Rebel Warthog
George Bush....................He bugs Gore
Ronald Wilson Reagan...........A long-insane Warlord
Margaret Thatcher..............That great charmer
The Conservative Party.........Teacher in vast poverty

And the grand finale:

"That's one small step for a man,
one giant leap for mankind." -- Neil A. Armstrong

becomes:

"A thin man ran; makes a large stride;
left planet, pins flag on moon! On to Mars!"