PodZinger on Wednesday officially launched its audio search service that's based on speech-recognition software that parent company BBN Technologies sells to super-secret government agencies, reports InternetNews. PodZinger crawls the web and daily adds podcasts to its index. Using speech-to-text technology it creates a text version of the audio index that's searchable by keyword. Searchers can click to listen from the PC, download the podcast or subscribe to it via RSS feed.

Alex Laats, president of BBN's Delta Division, said PodZinger's combination of audio and visual cues in the search results lets people determine relevance without having to listen to the audio. "Speech-to-text is not perfect, but by providing as much result as possible, you can assess whether it's a relevant or irrelevant result," he is quoted as saying.

PodZinger has also adopted a new business model: pay-per-click advertising. "It's a model that has been proven to be viable," Laats said. PodZinger runs both keyword and contextual advertising from Google. It is working on deals with large media organizations to use PodZinger search on their sites.