The crowdsourcing project "Writing History: Letters 1920-1934" is about the transcription of the unique letter collection of the Vienna City Library from this period. In contrast to historical printed works, which are now subjected to automatic full-text recognition as standard, this is still not so easy to do for manuscripts - especially when the documents come from many different writers, as in this case. If you want to join this new project, then have a look at the projects' website.