Charon

Charon is a central figure in the life of the underworld. Everyone must travel across the Acheron, the "river of woe," on their way to Hades. Charon is the only boatman on the river and as such Charon plays a key role in the life, or more accurately death, of every mortal. Charon charges a fee of an obolus, an ancient Greek coin. This is why the ancient Greeks buried their dead with a coin under the tongue. The exchange below demonstrates the importance of having a coins. The Corpse is only willing to help for decent ammount of money, enough to ferry himself and others across.

 DIONYSUS
Good.
And see they are carrying out a body now.

Here a CORPSE, wrapped in its grave-clothes, and lying on a bier, is carried across the stage.

Hallo! you there, you deadman, are you willing
To carry down our little traps to Hades?

CORPSE
What are they?

DIONYSUS
These.

CORPSE
Two drachmas for the job?

DIONYSUS
Nay, that's too much.

CORPSE
Out of the pathway, you!

DIONYSUS
Beshrew thee, stop: may-be we'll strike a bargain.

CORPSE
Pay me two drachmas, or it's no use talking.

DIONYSUS
One and a half.

CORPSE
I'd liefer live again I

XANTHIAS
How absolute the knave is! He be hanged!
I'll go myself.

http://www.pantheon.org/articles/c/charon.html