If you don't do much pc gaming then the Mac becomes a very good alternative. The iWorks suite is an excellent set of apps for everyday users. If you need MS Office there's MS Office 2008 for Mac. Otherwise, there's a good selection of opensource and commercial software plus even some games, a lot more games than some people might think.

We use our Mac Minis mainly for surfing the web or doing very light work. I still do most of my video-editing and flight-simming on the pc.