Another brick technique I have seen well executed, yet controvercial is foam-mold sheets. I have seen this method used for applications that are on curved set walls and also seen cave rock wall done this way, quite effectively.
The Sculptors carve a template sheet out of dense foam and create a mold from it. Then an insulation-foam blower type contractor is brought in to blast out sheets of foam rock/brick from the finished mold. Once the foam is set, the sheets are peeled from the mold, and pinned to the set wall.
Although this method creates a quick scenic wall with minimal supervision and minimal skill level for the most part, it is undeniably one of the most toxic of methods. Its toxic for the contractor, the labourers helping him and the scenics using the final product.
And its horribly non-environmentally friendly.
I try to avoid this method at all costs.