Recently I went on the Miller Brewery Tour in Milwaukee. You can get more information about the tour here. The tour is free and highly recommended.
After a short 10 minute movie featuring an animated "Fredrick Miller", the German immigrant who purchased Plank Road Brewery and turned it into what is now Miller Brewing (technically part of Miller / Coors), the tour begins.
The highly automated process that fills the bottles and cans is very impressive. You overlook these processes from a hallway above and they have a short movie on flat screen TV's at this stage in addition to narration from the tour guide.
You can see the beer stacked up in the huge distribution warehouse. There is a north and south building with a "beer bridge" and conveyer connecting the two facilities. In addition to brewing the usual beers here they also brew Leinenkugel's, and Pabst (gulp) on contract.
The buildings connected together are in "Miller Valley". As you can see it is a valley and this is apparently the worlds largest hand painted sign (per the guide, at least).
At the end you tour the caves where the original Frederick Miller stored his beer to keep it cool in the summer, packed in ice from nearby lakes.
They give three free samples at the end of the tour. For us it was Peroni, Miller Lite, and one of your choice. The beer actually tasted excellent, cold and right out of the keg. Someone I was touring with said that it seemed strange to get a "free lunch" (beer without paying and a free tour) and I said that I had paid for this tour hundreds and hundreds of times over in my lifetime of "investment" in Miller products.