Travis CI, if you haven't heard of it, is a free, hosted CI server for open source software. If you've been thinking about taking a break from Jenkins, Travis CI is a hot new tool that you should look at.
Travis CI recently added support for the OpenShift PaaS, so there is a new tutorial up on the OpenShift blog about how you can deploy a Java application to OpenShift using Travis CI. The sample application uses Spring, PostgreSQL and Tomcat 7. It's pretty simple. Only 11 short steps.