Concord Uses the Phet projects in some of our activities.
One way this is done is though OTrunk. There are 2 project otrunk-phet and otrunk-cck

These project depend on subparts of the entire phet source code tree.
An easy way to get these subpart projects is to use a projectset:

1. check out this project common/java/thirdparty/phet-simulations-java/ide/eclipse