This paper presents Attention Meter- a vision-based input toolkit for visual artist and designers to develop interactive art installation. This toolkit creates a text interpretation of human body gestures that can trivially be interpreted by any application to read this text file to make interactive use. This toolkit enables multiple head movements and expressions as input methods for Adobe Flash movie. A four day workshop demonstrated that Flash designers with no other user interface experience could competently make interactive spaces (i.e. TaiKer-KTV and ScreamMarket) based on body motion. Keywords Multimodal interaction, visual attention, interactivity ACM Classification Keywords H5.m. Information interfaces and presentation (e.g., HCI): Miscellaneous.