The Discovery Channel has a piece about the return of the Heidelberg fragment  of the Parthenon Frieze last week, covering not only the return, but what effect it might have on the campaign for the return of the Parthenon Marbles.
Discovery Channel 
Parthenon Piece Returned to Greece
Rossella Lorenzi, Discovery News
Sept. 7, 2006 — One of the oldest international cultural disputes, the battle over fragments taken from Greece’s Parthenon, has resurfaced with the return of a small fragment of the ancient monument by a German University.
The fragment consisted of a foot, carved from marble. It was taken nearly 200 years ago from the northern frieze of the the 5th century BC Parthenon. Its return to Greece on Monday was hailed by Greek officials as an important step toward the return of other fragments, many of which are kept at the British Museum in London.
Held at the University of Heidelberg for more than 130 years, the 3- by 5-inch relief sculpture was likely taken as a souvenir by a German visitor to Greece. It first appeared in the University’s inventory in 1871.
“This is a historic day. For the first time in almost 200 years, a precious piece of the Parthenon abroad is put in its original place,” Greek culture minister Giorgos Voulgarakis said as the sculpture was handed over by the university’s vice rector, Angelos Chaniotis.
In a statement, the University of Heidelberg said that the decision to return the fragment was “guided by the scholarly aim of promoting the unification of the Parthenon as a unique monument of world culture.”
The repatriation of the small fragment was hailed by Voulgarakis not only as a highly symbolic act, but as an unprecedented move in favor of the reunification of Greece’s artistic heritage.
“For the first time, the silent agreement among museums in possession of Parthenon sculptures has been broken,” he said.
The fearless horsemen, sprightly youths, lounging deities, belligerent centaurs and expressive horses carved by Phidias in the 5th century B.C. are scattered throughout several European museums, including the Louvre in Paris. But the bulk of the marbles are kept in London’s British Museum.
Greece contends that the 17 figures and 56 panels on display there were stolen in 1801 by Lord Elgin, British ambassador to the Ottoman Empire. The works have since become known as the Elgin marbles.
Britain claims that Lord Elgin had permission from the ruling Turkish authorities to take them.
The British also contend that the marbles have received better treatment at the British Museum, where they are safe from the polluted Athens air, which has damaged other Greek treasures.
Voulgarakis remarked that a space in the new Acropolis museum, which is due to be completed next year, has been reserved for the Parthenon sculptures.
“The demand for unification of the Parthenon sculptures originates exclusively by moral reasons and not by a nationalistic obsession,” he said.
The University of Heidelberg stressed in a statement that the transfer of the fragment is “a special case that should not be used as a precedence for other monuments and works of art.”
But the German gesture is likely to cause controversy among museums worldwide.
In 2002, when negotiations were underway to return a Parthenon fragment held at the Salinas Regional Archaeological Museum in Palermo, Sicily, directors of several major museums around the world deplored the move, saying in a statement that it could destabilize the entire museum system.