out church copied loud Paschal celebrations from the byzantine church a few hundred years ago - thanks, greek friends!http://www.youtube.com/watch?v=8uhW8Taf1z8
they start by singing Christos anesti (Christ has risen), alithos anesti (truly He has risen) 3 times, and then repeat it in arabic (or whatever language is appropriate).
then the priest and deacon continue (in proclamation and response form) by reading from psalm 23(24) (lift up you heads, o you rulers and be lifted up you everlasting doors, and the King of glory shall enter. Who is this King of glory? The Lord of Hosts, He is the King of glory).
the church is completely dark apart from a few candles at the front, to represent the women coming to the tomb to anoint Jesus' body.
i am sorry about the flash photography, that is not what usually happens! it should be dark and silent (we usually celebrate this saturday night just before midnight).
then all the lights go on and everyone yells and bangs and claps. the procession of subdeacons and clergy goes around the church with the icon of the resurrection singing 'Christ has risen from the dead, through death trampling on death etc.' (exact same words as sung by eastern orthodox church (we do it in greek, then in coptic) and also sung (interestingly) by romanian protestants).
excuse the slightly muted singing, the recording i found was from last year, and our patriarch had recently reposed (may God give him rest and reward)
this occurs about half way through the liturgy; the holy Body and Blood is still under the altar under the covering.