What colleges require both the SAT and ACT?
As far as score use policy, colleges vary all over the place. For the SAT, there is a handy chart about score use policies: http://professionals.collegeboard.com/profdownload/sat-score-use-practices-list.pdf . For the ACT, there is a description of various use policies, though not a list of what colleges do what: http://www.act.org/aap/infosys/scores.html