Lipikaar is a very good, simple and cost effective application for typing in Indian languages like Hindi, Bengali and Assamese, etc. The software is not very costly and single user licenses cost only Rs. 799/-. There is free Firefox add-on which enables the language support in Firefox and enables the user to type in Assamese as well. For Facebook users, this may work better than the native language options.
It is also available for trial use for three days.