The Shortcode Callback plugin allows you to use a [callback] shortcode to execute arbitrary PHP code wherever the shortcode is used.
Usage
Execute someFunction() and insert whatever it returns with the following shortcode: [callback function= »someFunction »]
Example shortcode to include a PHP file (the path is relative to WordPress’ ABSPATH), then insert the results of someFunction() where you used the shortcode: [callback include= »custom/filetoinclude.php » function= »someFunction »]
Shortcode example that includes a PHP file (the path is relative to WordPress’ ABSPATH), then passes a paramter to someFunction() and returns the results where you used the shortcode: [callback function= »someFunction » include= »custom/filetoinclude.php » param= »something »]
The format to call a class/method with the shortcode is exactly the same as above, except you specify the class::method in the « function » attribute of the shortcode. [callback function= »someClass::someFunction » include= »custom/filetoinclude.php » param= »something »]
There is an example (with PHP code) over here.