Some useful links:

The Homepage of Sage: www.sagemath.org

A site containing links for various computer tools for low-dimensional topology: CompuTop

The Knot Atlas: knotatlas.org

The Table of Knot invariants: KnotInfo

The GecoGedi Project Homepage: GecoGedi

An online version of Counter Examples in Tology: pi-Base

The homepage of Lukas Lewark, where one can find some computer programs for computing Khovanov-Rozansky homologies: Lukas Lewark's homepage'

The homepage of Marta Barigozzi: Marta Barigozzi's homepage'

E-Mail Addresses:
carlo [dot] collari [dot] math[at]gmail [dot] com
cc6706[at] nyu [dot] edu