Bhajan Kiirtan - a site dedicated to bhajans.

Dharma Central - An online information center dedicated to Sanatana Dharma, the world's most ancient continuously practiced spiritual culture. 

Hindu.org - Directory of Hindu resources online.

Hindu Baby Names - Hindu names and their meanings.

Hindu Calendar - online calendar with all the information on festivals, fasts, gods, goddesses, anniversaries, etc.

Hindu Universe - a site dedicated to Hinduism.  A huge portal with all kinds of information related to Hinduism.  A very complete site.

HinduBooks Universe - complete text of over 75 books on various aspects of Hinduism

Hindu Kids Universe - a site dedicated to Hindu children.

Hindu Web Universe - another Hindu portal.  Has various links to other Hindu sites.

Hindu Women's Universe - a site dedicated to Hindu women.

Hinduism Online - another mini portal.

MandirNet - listing of Hindu Temples around the world.

Mataji's Ultimate Site - Artis, cyber-pooja, prasad, and much more can be found here.

Vivaaha - a site dedicated to Hindu marriage.  Has matrimonials, mantras used in the ceremonies, types of marriages, etc.