label <- textGrob("A\nPlot\nLabel ",
                  x=0, just="left")
x <- seq(0.1, 0.9, length=50)
y <- runif(50, 0.1, 0.9)
gplot <- 
  gTree(
    children=gList(rectGrob(gp=gpar(col="gray60",
                                    fill="white")),
                   linesGrob(x, y), 
                   pointsGrob(x, y, pch=16, 
                              size=unit(1.5, "mm"))),
    vp=viewport(width=unit(1, "npc") - unit(5, "mm"), 
                height=unit(1, "npc") - unit(5, "mm")))



layout <- grid.layout(1, 2,
                      widths=unit(c(1, 1), 
                                  c("null", "grobwidth"),
                                  list(NULL, label)))



grid.rect(gp=gpar(col="gray60", fill="gray90"))
pushViewport(viewport(layout=layout))
pushViewport(viewport(layout.pos.col=2))
grid.draw(label)
popViewport()
pushViewport(viewport(layout.pos.col=1))
grid.draw(gplot)
popViewport(2)