Nico Nico Douga, a Japanese website similar to YouTube, played a fundamental role in the recognition and popularity of the software. Soon after Miku's release, Nico Nico Douga users started posting videos of songs created using her sound bank. According to Crypton, a popular video featuring Miku's super-deformed alter ego Hachune Miku singing and dancing to "Ievan Polkka" while spinning a Welsh onion in homage to Loituma Girl's original video (which led to Miku also being commonly associated with spring onions) demonstrated the potential of the software in multimedia content creation. As Miku's  recognition and popularity grew, Nico Nico Douga became a place for collaborative content creation. Popular original songs written by a user would inspire illustrations, animations in 2D and 3D, and remixes by other users. Some creators would show their unfinished work and ask for ideas.In September 2009, three figurines based on the derivative character "Hachune Miku" were launched in a rocket from the United States state of Nevada's Black Rock Desert, though it did not reach outer space. In late November 2009, a petition was launched in order to get a custom-made Hatsune Miku aluminium plate (8 cm × 12 cm, 3.1" × 4.7") made that would be used as a balancing weight for the Japanese Venus spacecraft explorer Akatsuki. Started by Hatsune Miku fan Sumio Morioka (also known as "chodenzi-P"), this project has received the backing of Dr. Seiichi Sakamoto of the Japan Aerospace Exploration Agency. On December 22, 2009, the petition exceeded the needed 10,000 signatures necessary to have the plates made. An original deadline of December 20, 2009, had been set to send in the petition, but due to a couple of delays in the Akatsuki project, a new deadline of January 6, 2010, was set; by this deadline, over 14,000 signatures had been received. On May 21, 2010 at 06:58:22 (JST), Akatsuki was launched, having three plates depicting Hatsune Miku and Hachune Miku in several monochrome images, composed of the miniature letters of the messages from the petition form etched in the plates. The UK 59th issue of the music and fashion magazine Clash featured Hatsune Miku as their cover star (using a real-life photo model), with a full feature on her.The Vocaloid software has also had a great influence on the character Black Rock Shooter, who looks like Hatsune Miku but is not linked to her by design. The character was made famous by the song "Black Rock Shooter", and a number of figurines have been made. An original video animation made by Ordet was streamed for free as part of a promotional campaign running from June 25 to August 31, 2010. A televised anime series aired in February 2012.In October 2011, Crypton showed on the official Hatsune Miku Facebook page a letter from the Japanese Minister of Economy for "contributing to the furtherance of the informatization by minister of economy." Geoffrey Cain of GlobalPost has argued that the phenomenon of Hatsune Miku is partly due to the love of Japanese for giving inanimate objects a soul, which is rooted in Shintoism or animism, but also in the long tradition of Karakuri ningyō or automated wooden puppets. Thus, Japanese are much more ready to accept a virtual character as "human".

Question: What kind of songs would encourage other people to create their own works?
Answer: Popular original songs written by a user