Googling open source licenses will give you several sites with comparisons of a fairly large number of the available open source licenses.
The GNU-GPL is the most well known license, but I would very carefully read it in it's entirety. A lot of legal opinions have repeatedly claimed that it is viral in nature, meaning that using software under it screws you over for making any money off the software in ANY fashion.
[ It isn't viral in nature, but it is the most restrictive open source license ]
The three I am most comfortable with are the CPL
[ Common Public License ]
BSD [ which is a modified MIT License ]
and one a friend has drawn up
[ essentially, it protects your copyright, but doesn't limit usage at all ]
the CCD Copywrite is:
since it's not listed anywhere at this time.
it isn't yet an official Open Source License.
Nor has it Officially been Released, but it is available for use under a work in progress status.