One type of project that people can do in an intentional community is selective breeding.
When a group selectively breeds for good traits, it is called eugenics; when a group selectively breeds for bad traits, it is called dysgenics; when a group selectively breeds for traits that are neither good nor bad, then it is neither eugenics nor dysgenics, and might be called 'neutral selective breeding'.
Successful selective breeding in an intentional community requires that the community be economically stable, have a substantial number of members, and consist mostly or entirely of committed life-long members. Eugenic selective breeding in particular can make good use of polyamory, because polyamorous reproduction allows a larger variety of valuable gene combinations to be produced.
There is forced selective breeding and there is voluntary selective breeding. In an intentional community, selective breeding would almost certainly be voluntary.
Selective breeding comes in both direct and indirect varieties. Direct selective breeding is straightforward: It consists of breeding particular males with particular females, and breeding some people while not breeding others.
Forced direct dysgenic breeding is very popular throughout the world, being the policy of about half of the world's countries. Countries that force direct dysgenic breeding onto their people include almost all of the muslim countries, almost all of the african countries, and almost all of the majority-catholic countries. Currently there are no countries in the world that force direct eugenic breeding onto their people.
Voluntary direct dysgenic breeding is also very popular throughout the world, being widely practiced in the same areas that forced direct dysgenic breeding is imposed. There are also some particular groups that practice voluntary direct dysgenic breeding; these are the quiverfull christians, the haredi jews, and various hard-line catholics and muslims, who propagate the genetic defect(s) that underlie their perverse, pathologically self-burdening character.
Unlike direct selective breeding, indirect selective breeding is, by it's very nature, almost invariably coercive, and it is even more popular and widespread than direct selective breeding. Indirect selective breeding consists of using direct government action, business oligopolies, educational institution oligopolies, other measures, or some coordination thereof, to manipulate people's conditions of imprisonment, property ownership, educational credentials, employment, income, sexual function, and/or other such conditions which effect a person's capacity to house offspring, provide for offspring, attract mates, have access to potential mates, and/or be capable and desiring of sex with mates. Like forced direct selective breeding, forced indirect selective breeding is primarily used for dysgenic purposes.