Arpan Shah has a nice post on his blog explaining how to use the DataFormWebPart to render search results from Live.com. It's a tutorial (with screenshots) on how to accomplish this using SharePoint Designer - at the heart of the post you'll learn to consume an RSS feed through the DFWP, step-by-step. With a little imagination you can apply the technique to bring in all sorts of external data to your SharePoint site, and still have the rich design tools for the DFWP available to you to customize the results view.
I would like to try this (as well as all the other ideas mentioned on this site) but I am unable to use SPD for more than a few minutes at a time without it crashing. I see in the comments under the initial blog entry there are many other people having the same problem. Is there a service pack or something coming out any time soon?
I have abandoned SPD for now. It caused far too much downtime over the course of my project.
Retomando el clásico recopilatorio de recursos y enlaces que sobre WSS 3.0 & MOSS venimos realizando