Yes. Open the project you want to bring the composition into. Do a “File–>Import”, go to the project is that has the composition in it that you want to import. Import the entire project. It will import the project as a composition (I think), as well as a folder that has all the elements of the project in it. Viola! The composition from that project is now in your new project, ready to be changed, dropped into a new comp, etc…
Michael.