Demos

You can use the animation package with the raster package. Here is a demo:

library(raster)
library(animation)
logo <- raster(system.file("external/rlogo.grd", package = "raster"), values = TRUE)
saveMovie(for (i in seq(1, 250, 20)) {
    logo1 <- logo
    logo1[logo1 < i] <- 0
    plot(logo1, main = i)
}, interval = 0.5, outdir = getwd(), movie.name = "logo.gif") 

Here is a demo to show you the real flexibility of the save*() functions. Let's take saveHTML() for example:

library(animation)
saveHTML({
   ## a custom file list on the Internet
   extList = c('http://yihui.name/cn/wp-content/uploads/1192203237_1.jpg',
               'http://yihui.name/cn/wp-content/uploads/1192203252_1.jpg',
               'http://yihui.name/cn/wp-content/uploads/1191914651_1.jpg')
   for (i in 1:length(extList)) {
       download.file(url = extList[i], destfile = sprintf(ani.options("img.fmt"), i), mode = 'wb')
   }
}, use.dev = FALSE, ani.width = 640, ani.height = 480, ani.type = 'jpg',
   interval = 2, single.opts = "'dwellMultiplier': 1")