The Bartleby edition of Gray's Anatomy of the Human Body is a free online version of the original hardback by Henry Gray (www.bartleby.com/107). It includes an index of 12 chapters, 1200 pictures, and more than 12,000 entries on every possible topic, from embryology to surface landmarks. The layout is intuitive and easy to use, and you can search by either keyword or topic. The only downside is that it is based on the 20th edition, last revised in 2000.
If you are after a lot of interactive content and videos, try the University of Michigan's Anatomy Learning Resources (http://anatomy.med.umich.edu). The anatomy tables list all key body structures, with essential information on each structure, and are great for revision. You can also view video of dissections and play learning games, such as “Who wants to be a millionaire doctor?” The many anatomical puzzles ask you to explain clinical cases based on