Find the next number in the sequence

1, 2, 6, 21, 88, __?

Can you write down eight eights so that they add up to one thousand?

Count the Triangle in the figure given below:

What does this Rebus Picture mean?

John said, "If yesterday was tomorrow, today would be Friday."

When did John make this statement?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

Can you find out the remainder when 3^300 is divided by 5?

For this puzzle, you might have to find logic in something illogical. But hey, it's fun and a healthy little break from your strenuous puzzle-solving sessions.

Can you decipher the meaning in the following cluster of letters?

ITIT,NCENTCENT

Two boys wish to cross a river. The only way to get to the other side is by boat, but that boat can only take one boy at a time. The boat cannot return on its own, there are no ropes or similar tricks, yet both boys manage to cross using the boat.

How?

A train full of passengers goes through a tunnel. When the train comes out from the other end, there is no single person on the train.

How did it happen?