Not really jokes, but puzzles
puzzle 1
[ame="http://www.youtube.com/watch?v=ZtAiz3Akizg"]YouTube- Puzzle: Using 6 straight lines make: 4 triangles and 3 squares or rectangles.[/ame]
puzzle 2
[ame="http://www.youtube.com/watch?v=BJS4TvjTDaI"]YouTube- Puzzle : Connect 9 dots with 4 straight lines[/ame]
puzzle 1
[ame="http://www.youtube.com/watch?v=ZtAiz3Akizg"]YouTube- Puzzle: Using 6 straight lines make: 4 triangles and 3 squares or rectangles.[/ame]
puzzle 2
[ame="http://www.youtube.com/watch?v=BJS4TvjTDaI"]YouTube- Puzzle : Connect 9 dots with 4 straight lines[/ame]