You have the possibility to send the same message to a large number of users at once with the mass message option. You will find it in the Messages panel, at the header next to the settings button. You have three groups of users that you can choose to send your message to: Fan Club subscribers, paying users who made any spending in the last 30 days, and Friends.
You can also send paid mass messages. These ones should contain content, either photos or videos that you can attach to your message (up to 5). You set the price of your choice and users will have to pay the amount to unlock the footage.
Notice that there's a limit of only one mass message per day. Moreover, you can only send one paid message in a row, so if for example you send a paid mass message today, tomorrow it will have to be a free one.