Microsoft Home Use Program - use more than one computer
Solution 1:
There is support in the HUP license (which is the same as a retail license for this discussion) for installing on two machines, a primary and a portable. This is described in the EULA.
One site where you can see this explained is here:
http://news.office-watch.com/t/n.aspx?articleid=872&zoneid=9
The EULA for Office 2007 with the relevant portion highlighted is here:
http://news.office-watch.com/t/n.aspx?articleid=734&zoneid=13
The EULAs for all Microsoft products can be found here:
http://www.microsoft.com/About/Legal/EN/US/IntellectualProperty/UseTerms/Default.aspx
If you look at the 2010 agreement you can see the same "portable device" language.