New title: Which aspects of LiveJournal are free?
All LiveJournal accounts, whether free or paid, can update journals, make comments, and perform basic customization of a journal's appearance, among other features. However, not all aspects of LiveJournal are free.
There are some features that are only available to Paid Accounts. This is necessary, because LiveJournal must pay for bandwidth and server costs. If a feature uses too much bandwidth, uses too much server processing power, or places too much of a strain upon the databases, it is reserved for Paid Accounts only. Additionally, some features are reserved for Paid Accounts to show our support for users who are supporting us. A complete list of these features can be found in http://www.livejournal.com/support/faqbrowse.bml?faqid=131.
While we would like nothing more than to be able to provide our full range of features to all LiveJournal users, simple economics prevent us from being able to. If you would like access to one of the Paid Account features, you will need to purchase a Paid Account. No exceptions can be made to this policy.
In order to create a LiveJournal account, you will need an invite code. Invite codes were implemented to curb LiveJournal's rapid growth and to help prevent people from creating accounts for abusive purposes. See http://www.livejournal.com/support/faqbrowse.bml?faqid=104 for more details on creating an account.