I personally don't believe in taking lots of different suppliments because if you are eating a fresh, healthy, balanced diet then your body should be getting most of the nutrients it needs.
That being said, I do take a few carefully sourced suppliments that help me in certain ways.
Suppliments I take:
Celery and juniper is a natural anti-inflamatory that I take for my back issues, these are not taken on a regular basis, only when needed.
Glycine is a non-essential amino acid that helps detoxify the liver, encourages muscle tissue growth and converts glucose into energy. Your body does produce it's own glycine but I do find extra to be helpful to me.
Once a day multi-vitamin can assist in areas you may be lacking through diet and environmental issues, I find these are helpful for me for a couple of reasons one being that I don't eat red meat and sometimes don't get enough iron from what I eat.
There is definately a place for well chosen suppliments to suit your own body but there is also a lot of rubbish out there that you can waste your money on and have no benefits to you.