Since MS Office is so expensive and borrowing a copy would never be an option. Especially because MS is starting to check lisences and stuff during update, I've been using Open Office. I'm not a heavy user. Will create an occational document and will open an occational document sent to me and stuff. No big deal. Open Office is working REALLY REALLY REALLY well for me. It looks VERY MUCH like MS Office and naturally works just like it. So, there's no learning curve making the switch. My son does Powerpoint crap for school, and didn't notice any major difference there either. One of the most neatest things about it though, is that it has built right into it, the ability to create a PDF of your document. Which I REALLY like. OH, the even more cooler thing is of course that it's FREE!! They ask for donations, but there is no charge for it.
So, if you don't feel like spending the money on MS Office, and don't want to risk stealing it, Open Office is a REALLY REALLY REALLY good alternative.