No. Thunderbird is an email client, and what you ask for requires an email server. Thunderbird ''could'' use filters to forward messages to other email accounts, but I get the impression that you don't want or don't have other accounts, and furthermore, a straightforward "forward" from an email client would destroy the record of where the original message came from. You can set multiple Thunderbirds on different computers to access the same account, but even then it's possible your email provider will baulk at multiple concurrent connections.