Though it's not as fondly remembered as most of the classic Lucasarts/Lucasfilm adventures, The Dig is a personal favourite. Its amazing alien world, the brilliant sci-fi plot, the involved and excellently designed puzzles, the oppressive atmosphere, the stunning pixel art and that impressive soundtrack make it an absolute must-play. Hence, grabbing The Dig (DOS) via eBay might be a pretty great idea if you love your retro pointing-and-clicking.
Mind you, it's the boxed MS-DOS version of the game you'll be bidding on and it comes complete with CD, jewel case, manual and reference guide. Seller ships to most places worldwide.