The type of roman coin Jesus used to illustrate, division of service.

This is a very interesting artifact from this Bit of Scripture Messiah Jesus used:

"And they sent to him some of the Pharisees and some of the Herodians, to trap him in his talk. And they came and said to him, "Teacher, we know that you are true and do not care about anyone's opinion. For you are not swayed by appearances, but truly teach the way of God. Is it lawful to pay taxes to Caesar, or not? Should we pay them, or should we not?”

But, knowing their hypocrisy, he said to them, "Why put me to the test? Bring me a denarius and let me look at it.” And they brought one. And he said to them, "Whose likeness and inscription is this?” They said to him, "Caesar's.” Jesus said to them, "Render to Caesar the things that are Caesar's, and to God the things that are God's.” And they marveled at him."
Mark 12:13-17

here is an example of such a coin one may purchase, the plastic slab encasing it, is guarantee of the NGC's stamp of authenticity:

http://www.ebay.com/itm/Roman-Empire-Tribute-Penny-Tiberius-AD-14-37-AR-Denarius-NGC-Fine-SKU36406-/381328289328?hash=item58c8efee30

in Jesus love, neil

Neil, now thats my kind of topic!
But all kidding aside this coin could certainly be used in a sermon illustration pointing out the benefits of giving to your local religious leader who is representative of God's channel in most circles.