Microsoft Office Home and Student 2007 3-PC License for $84.99 shipped.  Here is a screenshot for your reference.  Note that you do NOT need to be a student to qualify.  The licensing terms specifically state that you can install it on 3 PCs (bottom of the page).  The programs include Word 2007, Excel 2007, PowerPoint 2007, and OneNote 2007.  For comparisons of different editions, here is a handy table that outlines them.