I believe the Episcopal Church and the larger Anglican Communion have formal relations with the various branches of Orthodoxy. Though many differences still separate us, we consider each other brothers and sisters in Christ.
However, in the Episcopal Church, any baptised Christian can receive the sacrament of Holy Communion...regardless of age or denomination. An Episcopalian or Anglican may not receive the sacrament in any Orthodox Church.
Heck I was invited to receive the sacrament in your let-us love-everyone-no-matter-how-vile sect JS, as a godless one (I think maybe that outfit that hosted that fund raiser for Hagan got their name from reading my posts actually), and accepted. I like ritual for its own sake. Belief is beside the point - for me.
That's a sticking point in the Anglican Communion...Holy Communion for the unbaptized or for those who do not profess faith in Jesus Christ. The way it is supposed to be done is this -- EVERYONE is welcome to come to the altar, the baptized and professing believers to receive the sacrament and the unbaptized to receive a blessing from the priest.
But many Episcopal and Anglican clergy rebel against this. I actually come down fairly conservative on this point...I want everyone to feel welcome, but I would reserve the sacrament for those who profess faith in Christ. Ironically, this is not splitting the church. It should be splitting us, but we're too busy wringing our hands over homosexuals to think about much of anything else.
Please know -- I do not consider myself or any Christian to be superior to, preferable to or in anyway better than you or any Atheist or member of another religion. Few things among Christians trouble me more than the "we're the saints and you're the ain'ts so neener neener" attitude.
But I do think the sacrament should be reserved for those who actually believe in it.