Today, Apple lauched the iCloud website. From the iCloud website you can check your @me.com email, manage your contacts, manage your calendar, go to Find my iPhone, and use the new iWork beta. If you happen to be an old MobileMe customer, when logging in, you will be presented with the option to move your account to iCloud.
Since iCloud is still in beta, this service is only available if you already have an @me.com email address. Once iCloud is out of beta, it is probable that you will be able to sign up for iCloud on the website.
