What musical instruments were used in ancient Greek times?

The Greeks had a variety of instruments, such as the flute, the lyre, the harp, drums, cymbals, and castanets. There were also several horns (wind instruments). A detailed list can be found at:

It was Pythagoras, famous for his geometric theories, who also figured out the ratio for tones in a musical scale.

See also:

Questions and Answers regarding Instrumental Music
Sermons regarding Instrumental Music