Reducing the size of a black-and-white scanned pdf

I have a 352 page pdf that is a scan of a black-and-white text. The file size is 60.9 MB, which seems excessively large too me. (Is it indeed?)

Is there an easy way to convert this file to a more compressed one?

Edit. Here's a little sample:

60MB is probably OK for a greyscale scan of 350 pages. I have some 100pg color scans that clock around 30MB. If you meant it's actually black and white (and no grey) then it's definitely too big.

Preview is probably a bad tool to try to get the file size down without hurting image quality. The only tools available will resample the image to a lower resolution. What I use in a case like this is Acrobat Pro, which will let me convert the compression of the embedded scans to JPEG2000, which can save a lot of space over normal JPEG and retain quality.

A great PDF compressor is Ghostscript (gs), which is native in most Linux distributions and easily installable for Mac OS X and Windows.

Daniel summarizes summarizes it best here, with the key quote being his preferred options:

gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dNOPAUSE -dQUIET -dBATCH \
    -sOutputFile=foo-compressed.pdf foo.pdf