Caution: even if your outgoing email list has been scrubbed of bad/invalid addresses, you are still subject to LP's hourly limit of 300 emails. Lunarpages does not wish to become known as a source of spam emails, and will take measures to shut down abusive accounts! Please do not use an LP account for spamming.
Note that signup for newsletters and other such bulk mailings should be opt-in, where the target must explicitly request such mailings by checking a box or filling in their email address. In an increasing number of jurisdictions (including the E.U.), automatic signup, opt-out, having to uncheck a box, or any other method that requires the target to take explicit action to not receive emails is illegal!