FreeTextBox is no longer being actively developed and both the control and source are free to download. http://www.freetextbox.com/
Because the FreeTextBox official webside index page's download link is dead, the file here is download from http://www.freetextbox.com/download/download.aspx?filename=FTBv3-3-1.zip
I don't have the copyright. Just for study.