Having multiple domain names has quiet aroused the interest of other webmasters. But for those who have a better knowledge of the overall web marketing process, this is not a good idea at all!
Website owners who dont have better understanding of the search engines and the entire internet business may have thought over having another domain or domains for the purpose of having multiple listings on the search results. Thinking they can spam the search engines with slightly different domain names, these webmasters dont know what they are doing. It is basically spamming.
First you have to consider the reason behind the new domain. If it is solely for the purpose of being more visible on the search results, forget it. You can always optimize the existing site and still get better visibility. If you need to add more product information or advertisement on the site, you can always do this by adding more pages. No need for another domain.
Remember that each page of your site is a gateway to the other pages. There is a high chance of getting them ranked highly, all you need is an effective optimization process not another domain. Each of these pages can actually rank well on the search engines and no need to trick the search engines with another domain.
Instead of thinking for another domain name, you can decide on getting keyword rich title tags, website content and inbound links. These will guarantee your site a higher ranking on the result pages. Make your site relevant and good ranking will soon follow.
Having another domain is not the only way to get higher ranking and visibility. Instead of thinking about it, divert your attention on effective ways to optimize your site. There are just a number of other options.
Now you know that you don't need another domain just to play "tricks" on the search engine! So if ever you are actually thinking of having mulitple domains now, cut it out!