After long searching (years) for a reasonably functional open source viewer for the Mac; iRad is a refreshing surprise. Not only does it have the right tools for a real world radiology environment, it is integrated with an actual open source PACS which also runs on Mac architecture. This is a fact which I missed when I first looked at iRad a year ago. Not only does the SCP function as a receive station for images sent from other PACS (spelled "teleradiolgy") but makes a full IHE compliant PACS service available for archiving, retrieval, distribution, printing, RIS & HL7 integration, etc., etc. And you can't beat the price.