Venue Communications, Inc. offers WebDAV Calendar Hosting in both standard and Secure Sockets Layer (SSL).
If your calendar contains private information you may want to choose the SSL option. Secure Sockets Layer provides authentication and communications privacy over the Internet using cryptography. All data being transmitted between your computer and the server will be encrypted.
SSL is compatible with Apple's iCal, Mozilla Sunbird and any other Calendar software using .ics files and capable of publishing to a WebDAV server.