I'm hearing some buzz about a 90-day offer going on in Australia. If you are a student at one of about 30 universities, you can get the "Ultimate" edition of Office 2007 (includes OneNote!) for AUS$75 which is about 5% of what it costs to buy if you were to pay full price (which no one does of course, but it is still an amazing deal). Alternatively you can "rent to own" for AUS$25/yr for three years. Too good to be true? No, it's for real.
You can read more here: http://www.itsnotcheating.com.au/form.asp
And bland details here: http://www.microsoft.com/australia/education/unistudentoffer/default.mspx
I looked into this a bit and while some people in Australia are speculating a lot about why this promotion is going on, the background is pretty simple. The fact is most university students can already get Office for about this price from their university because their university negotiated it into their purchase agreement on behalf of the students. The students just don't know it. And the universities find it a hassle to get the product out to students because they have to do all the muck work: getting boxes stocked, checking IDs, making sure people don't buy more than one, etc. So they don't promote it. This trial offer in Australia is experimenting with Microsoft handling the work. As long as the particular university you attend has purchased the right for all its students to have the software, you can just get a licence key directly from Microsoft. The difference is that the students have to get their own bits (usually download the free trial).
Pretty good deal. If you're a student in Australia, go for it!
I don't know anything about whether this program will be extended or offered in more places, so please don't ask, OK?