I just bought an eReader that supports PDFs and have been saving articles I find online as PDFs to read later. However, I wanted to have a designated directory on my Mac for my PDFs.
To add this as an additional option to the PDF drop down menu in the print dialog, go to home ~/Library/PDF Services and drop in an alias of the directory where you want save your files.
Alternatively, you can create a symbolic link with terminal in that directory like this:
ln -s ~/Documents/Readinglist/ "Save PDF to Reading List"
Now you have a quick easy way to save your articles for reading later.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20090817002247614