I appreciate all the other answers, but Didzis Elferts's comment on the OP connected to the answer that I found easiest to implement.
library(ggplot2)
p1 <- qplot(x=wt,y=mpg,geom="point",main="Scatterplot of wt vs. mpg", data=mtcars)
p2 <- qplot(x=wt,y=disp,geom="point",main="Scatterplot of wt vs disp", data=mtcars)
p3 <- qplot(wt,data=mtcars)
p4 <- qplot(wt,mpg,data=mtcars,geom="boxplot")
p5 <- qplot(wt,data=mtcars)
p6 <- qplot(mpg,data=mtcars)
p7 <- qplot(disp,data=mtcars)
p8 <- qplot(disp, y=..density.., geom="density", data=mtcars)
p9 <- qplot(mpg, y=..density.., geom="density", data=mtcars)
vplayout <- function(x, y) viewport(layout.pos.row = x, layout.pos.col = y)
grid.newpage()
pushViewport(viewport(layout = grid.layout(3, 5))) # 3 rows, 5 columns
print(p1, vp = vplayout(1:2, 1:3)) # the big plot covers rows 1:2 and cols 1:3
print(p2, vp = vplayout(1, 4))
print(p3, vp = vplayout(1, 5))
print(p4, vp = vplayout(2, 4))
print(p5, vp = vplayout(2, 5))
print(p6, vp = vplayout(3, 1))
print(p7, vp = vplayout(3, 2))
print(p8, vp = vplayout(3, 3))
print(p9, vp = vplayout(3, 4:5))