Stimpy!
      .    _  .     _____________ 
      |\_|/__/|    /             \ 
     / / \/ \  \  / Happy! Happy! \      
    /__|O||O|__ \ \   Joy! Joy!   / 
   |/_ \_/\_/ _\ | \  ___________/      
   | | (____) | ||  |/                       
   \/\___/\__/  // _/
   (_/         ||        
    |          ||\       
     \        //_/   
      \______//      
     __|| __||      
    (____(____)      

A Cthulhoid something:
               //\\--x
        \\___//   //\\
     > / 0 --\---//  \\
      | o =( [|}      xx
      | o =( [|}
     > \ 0 --/ --\\
        //~~~\\    \\_-_-_-o\
               \\
          xx  //
            \\
            \\

The classic "Bob"'s head:

                                       ,,,,""""""""",,,,
                                    ;^^~      %  %%      ~^^:
                                  ;^     ~^  %  %% % % % I  ~^:
                                 :            ~ ~~ ~I          :
                                ;'                  '  _,w%<    :
                                :     %%%%%%%%w___,w%%%%%%%%  %  :
                                :     %%%%%%%%%%%%%%%%%%%%%%  I  ;
                                :     %%%%%%%%%%%%%%%%%%%%*%[ i  :
                                :     %%%%%%%%%%%%%%%%%%%%[][ | ]:
    ________________________   :      ~_,,_ ~%%%%%%%~ ____~ %    ;
   /         If You         \  :     _~ ,  ,  `%%%~  _  _`% ]L  J;
  | offer it, they will buy  |  :  , %%w%ww+   %%%ww``,,%w% ][  :
   \________________________/   :,  %%%%www%%% %%%%%%%ww%%%%%[  :
                                :_||  %%%%%%P' %%P%%%%%%%%%%%[|c:
                     ()          :w| '@@P~  P]@@@-~, ~Y@@^'],:
                                 :[   _        _J@@Tk     ]]:
                       ()          :,@ @@, c,,,,,,,y ,w@@[ ,:
                          O         : i @w   ====--_@@@@@  :
                            o        :`,P~ _ ~^^^^Y@@@@@  :
                              .:^^=^@@^   ^' ,ww,w@@@@@ _:
                             .:_xJ~ ~   ,    @@@@@@@P~_:
                             :   @,   ,: :,_____   _,J:
                             :L  `' ,:
                                """

Here're a couple for anyone who feels a need to exercise a little "control":

\ ! /
                          ___
                  O @----!___!
                  !/     * O *
                  !       \!/
                 / \       !
               /     \    / \
 
                ZAAAAAPPPPPP!!!!
 
  This thread has just been ZAPPED as being OFF TOPIC!




     __               /-------------------------\
    /  \             / Stay out of the dog-house,\ 
   /|oo \           /don't post off-topic messages\ 
  (_|  /_)         /and don't reply to them either.\ 
   _`@/_ \        /---------------------------------\
  | (*) |  \   ))   |                             | 
  |__U__| /  \//    |             /^\             |
   _//|| _\   /     |            |   |            |
  (_/(_|(____/      |            |   |            |
  

This is a very sick one, but it amuzes me:


        _________________   ()(()))    
       /YES,YES OH YES!!!\   |##  )   
      |    OH GOD I LOVE  \ /_    |     
       \ TO FUCK SHEEP!!!_/\\ |O ) \        ***************************
        /          \         \___/ \       | If you love something,    |
        | BAAAAAAH!|          __|  _\      | Let it go,                |
        \ _________/         |    /  |     | If it doesn't come back   |
        ||                   |   |   |     | Hunt it down and kill it! |
        //                   |   /  /|      ***************************        
    ****                 ____----/  / |      
   ****** ***********  /_\_)______/  /         
   *00 /|*******************  |     |  
   *@  **|****************----|     \          
   * - **/****************---(_)     |          
    **** **       *******     |     //          
     | | |         | | |      |    // _        
     | | |         | | |      |   /--( \__      
     |^|^|         |^|^|      \__________/   
____________________________________________________________________
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/