The merits of information technology for the archiving of cultural heritage have been long acknowledged. The challenge now is to realise the communicative potential of information technology for the development of new structures. This is exactly the concern of Mixed Realities as communication levels between reality and virtuality, which offer an open space for visions and creative ways of dealing with the past. The i2tv (interactive Internet-TV) concept addresses this issue as an electronic arena combining interaction in real space with actions of Internet participants into a new framework of cultural participation and production. The i2tv system integrates Internet-based multi-user interaction and awareness with broadcast technologies such as Internet streaming and Virtual Studio, and with technologies for mixed reality in shared physical space. This paper presents two concrete models for cultural events enabled by i2tv and discusses the experiences with their public trials: (1) The Memora Futura Symposium extends the historical format of participation in public discussion into a networked Mixed Reality agora visualising a memory space of collective experience; (2) The "Ottos Mops" distributed play based on sound poetry of Ernst Jandl, develops a model of distributed participatory theatre making on-line participants active producers of new content and an integral part of the situation on-site. The combination of 3D Internet environments with digital TV, mobile communication interfaces and medial staging on-site, demonstrates the integration of the participatory model of the Internet and the passive broadcast model of TV into a new convergent unit - interactive Mixed Reality TV.