On Monday Apple deposited a complaint against a Californian company that offered on many sites copies of the MagSafe chargers.
As you can see it, the product is practically identical to that of Apple, including the magnetized connector. However, contrary to the connectors with which the Powerbook and iBook were equipped, Apple patented this MagSafe connector and nobody can copy it without permission, that is systematically refused. The honest companies marketing of the external batteries are obliged of cannibaliser Apple chargers to recover this end in all legality.
Even if the quality of the copies are good, we find it regrettable that one cannot bypass the high Apple tariffs.