Sometime ago, I was doing work for a client that required mult-select picklists to be displayed as checkboxes on a Force.com site. The Visualforce pages were client facing and therefore needed a consistent look and feel with optimal UX.
It was quite an effort to get this functionality together as doing this requires a Class, Visualforce & a Test Class. So, in this post i'm sharing code of the prototype I developed in my sandbox environment.
<!-----Visualforcepage: Input a Valid record ID for the page to work ----->
To copy the code /to get more details use the link below.