Ridina founded and runs Hlasohled - a centre for working with the human voice - from 2006 to the present
The music for the Giant Puppets performances in Pilsen, together with Petr Tichý, Aliaksandr Yasinský, Ondřej Kabrna and Miloš Dvořáček.
Joint improvisation with Bobby McFerrin during his concert in Prague.
Duet with Vladimir 518 - CD Gorila vs Architekt, track Nespoutáš mně - 2007. See www.biggboss.cz
Collaboration with Tomáš Dvořák/Floex - CD Pocustone, Floexí band from 2001-4), see, for example, the interactive game Candi ski
Guesting on Fontanel CD by Monika Načeva, 2001
Joint concerts and improvisation with Jaroslav Kořán. V. and I. Havlový, Vladimír Václavek, Ondřej Smejkal, Petr Nikl, Sylvia Krobová, etc. ..
Cooperation with Jan P. Muchow on music for the film Pusinky (Dolls), directed by Karin Babinská (2007)
Cooperation with Vladimír Merta on music for the film Fimfárum II, directed by V. Pospíšilová, B. Pojar and A. Klimt (2005)
Cooperation with Jan Ponocný on music for the film Vaterland, directed by David Jařab (2004)
Solo project Hlasokraj (Voicescapes) - won Newcomer of the Year 2006 - Next Wave Awards
Cooperation with Palitchi a group of fire magicians - http://www.palitchi.org/
Musical cooperation - performance with Theatre Continuo Kratochvílení from 1999 - 2006, Kratochvíle Chateau, South Bohemia, see http://www.continuo.cz/
Cooperation with Petr Tichý and Markéta Kotková - setting shadow plays to music, 2011
Authorial and music collaboration - performances It’s so lovely, isn’t it? together with Petra Ernyeiová and Adela Stodolová, Alfred ve dvoře Theatre, 2003
Baba jaga - authorial and musical collaboration on puppet shows, created along with Radka Mizerová and Robert Smolík. Premiere: 28 September 2005 in the Garden in Jičín
Musical collaboration on a movement performance The Mayfly’s Life (concept Eva Blahová, dance Natalie Slováčková)
Guested as an external teacher at DAMU.
Regularly runs voice workshops both for the public and for professionals (see VOICE WORKSHOPS)