A new site focused on the Literary Agent, called The Chronicles of Sir Arthur Conan Doyle is up and running. It features a Conan Doyle quote of the day, a store called the Baker Street Bazaar, and sections on Doyle's life and works.
The coolest feature is the ability to send Sherlock Holmes e-cards with Canonical quotes. There are holiday and birthday themes, and just general occasion options.
While you're at it, two other excellent Conan Doyle sites are the Arthur Conan Doyle Society and the Friends of the Arthur Conan Doyle Collection at the Toronto Public Library.