program to manipulate orthog axes ?

[Peter Turner]

Anyone know if there is a public domain program that will
translate and rotate cartesian coordinates -
preferably with a very easy to use interface (mouse driven)
and preferably for a PC ? 

We've got a post grad here in a hurray to use small molecule
crystal structure coordinates to do some EXAFS modelling and
she needs to centre and align the coordinate axes.

Hope that makes sense.

Thanks, Peter.