Bluehost enforces a maximum outgoing email per limit on their service. Most tasks, such as personal email, and mass mailings can easily be routed through other mail servers. As long as the process sending the mail does not reside on the server, then it's as simple as changing the settings to use another mail service.
If your application has to run on the server, such as a web application, forum,
business contact tracker, or cms, then you are out of luck. There is no way to
send email to an outside server from Bluehost. Port 25 is blocked, because that
would be open season for spammers. Any sane shared hosting company would
enforce the same policy. The only way to get an email out to the rest of the
world is to use either the sendmail binary, or connect to port 25 on
localhost to send a message.
There ...