Outlook 2011 - how to run on 2 macs?

You need to stop using a POP account and switch to either IMAP or Exchange.

POP downloads emails from the inbox, while IMAP and Exchange will sync it.

That depends on what your purchased. Office 2011 requires activation. You would need a 2 Pack in order to use on both computers. In the past you could install on one desktop and one laptop but that was discontinued in Office 2011.

I don't believe you can purchase another install once you purchase the 1 pack. The H&S version no longer comes with an email client so you can't use that to get around the requirements for installing on more than one computer.

An option would be to switch to IMAP and use your browser for viewing mail while you are traveling. If your provider doesn't offer IMAP you can setup Gmail as IMAP had have it forward your POP account so you will have access to those emails while traveling.

I'd agree with the above. If you're not looking to buy another license, i'd recommend using a browser to read and reply to e-mails while on the road. And the advice about switching away from POP is good advice...