General Relativity.

• Curved space and geodesics around a star.

The Arrow of Time. Time evolution with decreasing entropy. (The initial states are special!)

• Interacting particles
  
• Reversible cellular automatons:
  • "Life" combined with the second order technique
    
  • Fredkin's Billiard Ball Machine
    

Order from disorder. (Random initial states.)

• "Gömböcök." Little dumplings emerge from a gas of particles:
  • Formation of dumplings that eat up everything.
  • Formation of socially behaving dumplings. (They group together and do not eat their companions.)