Twitter username style urls: twitter.com/sineld

routes.php

<?php
// Source: http://www.everyonecanweb.com/snippet/view/28

Route::filter('before', function()
{
    	// Direct user to clouddueling.com/nickname
    	$nickname = URI::segment( 1 );
	if( !in_array( $nickname, Controller::detect() ) )
	{
    		$user = User::where_nickname( $nickname )->first();
    		if( !is_null( $user ) )
       			return Controller::call( 'user@profile', array( $user->id ) );
	}
});