Multi-Site | Multi-Domain?
One way to do this, is use different environments for each domain and set a variable (for instance, an entry ID) for each environment. So, your config/general.php would look something like this:

return array(
   '*' =&gt; array(
       // Every config setting that's the same for all domains (like devMode, omitScriptNameInUrls, etc.
   ),
   'firstDomain.com' =&gt; array(
       'siteUrl' =&gt; 'http://www.firstDomain.com/',
       'environmentVariables' =&gt; array(
           'baseUrl' =&gt; 'http://www.firstDomain.com/', // For use in asset source, for example
           'basePath' =&gt; '/path/to/public/folder/', // Same for this
           'entryId' =&gt; 5 // Or whatever the ID of your entry is
       ),
   ),
   'secondDomain.com' =&gt; array(
       'siteUrl' =&gt; 'http://www.secondDomain.com/',
       'environmentVariables' =&gt; array(
           'baseUrl' =&gt; 'http://www.secondDomain.com/', // For use in asset source, for example
           'basePath' =&gt; '/path/to/public/folder/', // Same for this
           'entryId' =&gt; 8 // Or whatever the ID of your entry is
       ),
   ),
);


Then, in your template (entry.html or whatever file you use as your section's template), you get the data like this:

{% set entry = craft.entries.id(craft.config.environmentVariables['entryId']).first() %}

&lt;h4&gt;{{ entry.title }}&lt;/h4&gt;