post_front_page.php

<?php
/*
Plugin Name: Post Front Page
Plugin URI: http://premium.wpmudev.org
Description: Allows a post (not page) to become the front page of a WordPress site
Author: Chris Knowles
Version: 1.0
Author URI: http://twitter.com/ChrisKnowles
*/

// intercept the main query
function pfp_pre_get_posts ( $query ) {
	
	// only interested in home page and the main query
	if ( !$query->is_home() || !$query->is_main_query() ) return;
	
        // default args - most recent post
	$args = 'posts_per_page=1&order=DESC&orderby=date&ignore_sticky_posts=true';
	
        // check for sticky posts	
	$sticky = get_option( 'sticky_posts' );

        // have sticky posts so use them			
	if ( $sticky != '' ) {
		$args = 'p=' . $sticky[0];
	}
			
	// clear the current query
	$query->init();

        // parse in the new arguments
	$query->parse_query( $args );
		
}

add_action( 'pre_get_posts' , 'pfp_pre_get_posts' );

?>

Hi @pommiegranit !
I tried this plugin on my site. Doesn't work. I guess because I am 4 years late!
I am using the twentysixeen theme. Is there anything I can do to make this work?
I have been looking for this functionality for a few months now.