Creative commons (CC) are a set of open licences, which allow you to tag your work for reuse under certain conditions.
The Manufacturing Pasts project is committed to releasing digitised content and open educational resources under an open licence. We therefore intend to use a CC licence, though exactly what type has yet to be decided.
At our recent project group meeting we were all agreed that at the very least we would require attribution (BY), so we will certainly be using that component. Another straightforward decision was to not use the No Derivatives (ND) component, as we want our resources to be reusable and included in other packages.
The debate regarding whether to permit commercial use of a work is wide ranging but, from personal experience, rights holders are more likely to permit re-use of their work under a CC licence if it can only be used for non-commercial (NC) purposes. I would therefore suggest a CC-BY-NC licence. It is worth noting that if people specifically want to use one of your works for commercial purposes, you can waive this requirement (providing you have the agreement of the relevant rights holders) in individual cases.
There is also a decision to be made as to whether to add the Share-Alike (SA) option (this allows others to distribute derivative works only under a licence identical to that governing your work). Although the SA option on the surface would ensure greater dissemination of our works, the option can also pose a problem with potential users. They may not be willing or able (due to institutional policies, or limitations on the use of other third party works) to make their final output available under a SA licence. As a result they may decide not to use re-use our works.
Finally, we have to decide whether to use a ported (country specific in terms of the legal requirements), or unported licence. The difficulty, as I understand it, is that as ported licences are country specific, their terms are not always well understood by users from other countries. Unported licences are more internationally transferable.
My recommendation would therefore be to use a Creative Commons, Attribution, Non-Commercial unported Licence (CC BY-NC), version 3.0.
 See Erik Moller’s Licences/NC http://freedomdefined.org/Licenses/NC and kuro5hin’s Eloquence posting Creative Commons -NC Licenses Considered Harmful http://www.kuro5hin.org/story/2005/9/11/16331/0655
 Adapted from CreativeCommons.org