Introducing an online collection library of sanskrit documents: http://sanskritdocuments.org/ a great collection for rare sanskrit books from India. It has work of many famous authours of their time like adi shankracharya. Lots of tools for sanskrit typing etc. you can find out in this portal. Its totally unique in the field of sanskrit the oldest language considered.

If you want to coin new words using Sanskrit language its a good resource for you, it will rock you if you have some knowledge. you have noted the our international language English has adopted  lots of words originated from India like avatar, guru, tantra and lot more which are very usual. those who are in language study or interested in ancient Indian, Nepal history will find it very useful for them or people in India or NRIs who are in Sanskrit study can found the documents from here. Other people who have keen interested in knowing ancient culture o doing any research on tantra can find many standardized texts here. You will find after study that many languages from words are mere subset or vey similar of sanskrit.