For the longest time I held off upgrading to Office 2007 because it was so expensive and 2003 worked just fine. This year I found a great deal linked through our school’s website.
Microsoft Canada has set up a site they’ve named The Ultimate Steal. Essentially you can buy Office 2007 Ultimate edition for $64 Canadian. It’s totally legit too because the TOC are from Microsoft.com.
I ordered a copy and they EMAIL you the product code 
The cool thing is there isn’t any restrictions on the license, I can use it commercially all I want. I’ll be buying a few copies through some of my friend’s emails for the cafe.
The only catch is you need a university/college registered email.