Script of the day

I'm really not sure how to explain how awesome this script is, but after many hours of trying to figure out how to reduce the size of a pdf file, here is the most amazing find of my day.

gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen -dNOPAUSE -dQUIET -dBATCH -sOutputFile=output.pdf input.pdf

This was able to convert my 6.4Mb file down to a measely 155Kb. Need I say more? :)

Now to make my day complete, if only I could find a means of being able to change the metadata inside the pdf file without having to download 3rd party software :( I just want to know how to view it.