I understand that one of the advantages, besides opening a Thai bank account and driving licence is being able to obtain Thai health insurance at a much reduced rate.

Does anyone have this health insurance and if so what companies in Thailand offer such a policy for foreign students.

Being a student will not enable you to get an individual private insurance policy at a lower rate AFAIK. However, most universities provide coverage for their students as part of the tuition, so check with the school in question. (If it is just a language school, it may not). If they do not provide any type of cover, then you will have to buy it and it will cost the same as it would if you were in Thailand for any other reason (which, if you are young, is not that much). BUPA Thailand is the most widely used private insurance here.