Directing several domain names to different sections of a main site

How do I do this?

[ace2000]

I have two competitors that sell products. On their websites they have several category pages such as widgets, gizmos, etc.

Each category on their site has good content, and since these categories are like sites within a site, my competitors have started buying domain names that point to each section, like widgets.com and gizmos.com.

Now when I do a Google search for a gizmos, I get their main site's gizmos page PLUS another domain that points to a category within their gizmos page, like gizmos.com. So they have multiple links in the SERPS for gizmos!

How is this done? Do I just buy domains and have them point to my site categories, or is there some type of cloaking going on?

[edited by: caveman at 12:29 am (utc) on Nov. 19, 2005]
[edit reason] Widgetized - no specifics please, per TOS [/edit]

[caveman]

If they have two sites ranking for the same term, with the purchased sites linking back to subpages of the main site, then they're obviously doing something to get the purchased sites to rank also. The possibilities as to how they might do that are nearly endless.

[ace2000]

I was wondering if anyone else could give me some more possibilities. If I just start buying a bunch of domains and linking them to parts of my site, will that work?

[webboy1]

I would have thought this would be classed as bad SEO practice. 2 URL's pointing to the exact same page?

Isn't this something sites are nowadays punished for?

I would have thought, if he was doing it, it would be via a 301 redirect - simply to keep the site out of trouble.

What would happen if you were punished and your main site de-listed. All you would have left to play with would be your page specific URL - which is no good for the rest of your site.

Maybe I have just misunderstood the situation?