e-dinar is a precious metal backed digital currency - http://www.e-dinar.com/
Gold backs the dinars and silver backs the dirhams.
Traditional Islamic dinar coins were 4.25 grams of "pure gold", but there is a modern initiative to introduce a new version intended for savings/circulation/settlement that will be 4.25 grams of .917 gold alloy.
You might want to talk to senbonzakura and the IBB folks - https://bitcointalk.org/index.php?topic=21732.0
. I think your services could be a great fit for partnership with Islamic Bank of Bitcoin (IBB). Maybe they could start a zakat service in e-dinars or something?
E-dinar charges relatively low fees compared to competitors. One issue with most gold-backed digital currency is that a robust market like the bitcoin marketplace (see https://bitcoin.it/wiki/Trade
since this is the newbie section) tends not to develop around the currency.
It has been suggested that this phenomenon is in some way related to "Gresham's Law", where people holding the gold-backed currency would rather spend fiat currency than gold money when given the choice.
Also, of course, bitcoin has the advantages of not being able to be confiscated or seized and not being able to be shut down.
E-dinar requires trust in the issuer company as well as that there won't be interference by gangsters/governments.
Bitcoin also has some great transparency e-dinar can't really match.
But word on the street is that e-dinar.com folks are good people, but do your own research of course.