Established in 2004, the Chithakar mailing list is one of the oldest and (perhaps) the largest mailing list in Hindi with over 500 members. Its a public group for Hindi
bloggers & people primarily interested in Indic computing. The group discusses technical and other issues
pertaining to usage of Hindi over Internet, though
you can have a civilized discussion on anything under the sun. More details & the Group Charter are available at https://sites.google.com/site/chitthakar.