OS - tan actually started out as a meme. It became very popular online so people cannot help but just appreciate it. The cute characters were used as an ad campaign for Internet Explorer which is why a lot of people are familiar with it. If you would like to relieve the time when you still saw those ads then you can make it in the form of seeing the new and upgraded version of one of the characters of the series. While the graphics may already be different, it will help you realize that things do change tremendously and if they do, they change for the better.