Safari, in a attempt to speed up web browsing, caches favicons for each site you visit. Over time, however, this potentially can make web browsing slower, rather than faster. Deleting these saved favicons just might make your web browsing a little faster. Obviously, caching these tiny icons does help, so deleting them too frequently will be counter productive. Delete them with the following command (and restart Safari):

# rm -r ~/Library/Safari/Icons

Using the code below, you can open a new Safari window for a given url (www.google.com).

tell application "Safari"

    make new document at beginning of documents

    set URL of document 1 to "http://www.google.com"

end tell