Various things with increasing seriousness from the top to the bottom:

• London Airport Announcements

  A wonderful delicacy from England

• The Wyoming Wind Sock

  It is very important to know always the windspeed. There are several ways to find it out.
  The Wyoming Wind Sock outside the National Weather Service Office Cheyenne, Wyoming is a really convincing one.

• The Journey of Lukanga Mukara into the Innermost of Germany

  He came from far away and found a really strange world.
  His observatuions from 1912 are still surprisingly valid.

• The Pac-Man Illusion

  In every case our brain is between the reality and the view: The Pac-Man Illusion or the Lilac Chaser of Jeremy Hinton. Isn't it fascinating?
  The webpage Optical Illusions and Visual Phenomenia of Michael Bach has more of these things.

• The BMLwalker

  Bio Motion Lab shows with the BMLwalker, how few information is necessary for our brain to access peoples reliably.

  Meanwhile their WebGL walker is a really spectacular improvement. Better to meet him on the screen only.

• Alphametic Solver

  The Alphametic is an equation consisting of alphabetic characters instead of numeric ones.
  For calculating the equation the alphabetic characters have to be exchanged by numbers.
  Therefore there are up to ten different letters for the possible digits in the equation.
  After changing back the characters into numbers only one single combination gives a proper result of the Alphametic.

  The Alphametic Solver can also be used to verify Alphametics. At the end the application reports the necessary runtime in milliseconds.

  The runtime depends on the speed and the load of the computer, the comlexity and length of the Alphametic, and last but not least on the speed of the used program or the used browser. The graphical overview shows these aspects.

  These examples might help to understand the special properties of Alphametics.

• Sudoku Solver

  Have you ever solved a Sudoku? Was the solution right? Was it the only solution? Concerning the high number of possible variants it is a really challenging question.

  Why asking such a silly question? It is completely unnecessary. Everybody knows that a Sudoku has only one solution.

  If you don't believe in this or a proper solution can't be found in time, the Sudoku Solver will help. It doesn't surrender before it has seen evey single possibiliy. Except if it has found already ten solutions. Then it simply breaks. Otherwise the cycle counter shows the complexity of the Sudoku.

• Login-Attempts Port 22 (SSH)

  A SSH server is running on the computer and port 22 is enabled.
  Someones somewhere have found the access. Apparently they are trying to login there.

  What, if they are successful?

• Time is running! How many seconds are left? Here is the answer.