After April 7th, the new NIH Public Access Policy will require you to submit any articles which arise from NIH Funding to NIH's PubMed Central, where they will be freely and permanently accessible to all so that they might better advance science and improve health. Before that, however, you'll need to make sure you don't sign away the necessary rights in the journal's author agreement.
The University Libraries and the Sponsored Projects Administration are prepared to help. Questions about the policy can be sent to nihpublicaccess@umn.edu. We can help you ensure you have the necessary rights, guide you through the submission process, and help you understand how to cite your articles in future applications and progress reports. For more information, go to:
http://www.lib.umn.edu/scholcom/NIHaccess.phtml