If you've worked in a large hospital system, you've probably run across Epic. You probably won't see this Electronic Health Record (EHR) solution used in solo or small outpatient practices. Epic is mainly used in larger hospital systems. If you're looking for an enterprise-level EHR, then you've probably evaluated Epic (along with McKesson, AllScripts, Epic, Cerner, Meditech, GE, etc.).
Epic is based in Verona, Wisconsin and they are adding 900 new jobs. The rapid growth in health IT is truly exciting, but I often wonder if we're going to see a massive "bubble effect" in this whole industry. Several years from now, most physicians will be operating on digital systems, so new implementations won't be occurring very much, but system upgrades and overhauls are what we're likely to see in the future.
Interested in a career in health IT? Get to know the major players and attend large health IT conferences like HIMSS (Healthcare Information and Management Systems Society) which is coming up in Feb.