You can download the trial version of Office 2003 as many times as you like.
Whether you will be able to install all those instances on one machine, is
debatable. Otherwise, there ARE no downloads od Office unless you have an
MSDN subscription.
Downloading and Installing are 2 different things. You can download as many times as you wish but to Install what you downloaded can be done once only depending on what you want to install . Trial software only once. You cannot keep installing after it expires over and over . After the Trial period expired you would need to convert it to a paid version for having it to work
And if you mean install from CD, as many times as you like, though you may
have to use telephone activation
NB OEM and Retail versions have different criteria