I just discovered that you can download a PDF file of the unabridged 8th revised edition (1897) of the Liddell and Scott Greek-English Lexicon at Open Library. I don’t have a hard copy of any edition of Liddell and Scott, so this will come in quite handy. I assume that many of you will find it useful too. If you follow the link I’ve provided, you will also find several older editions.
UPDATE: My colleague at AMU, Joseph Yarbrough, who teaches in our Classics Department, has pointed out that there are two excellent and searchable Greek lexicons here and here. These will be much easier to use than a PDF file (although I do like the PDF because it’s a little more book-like; strange, I know).