HeinOnline just keeps getting better

Originally they were a great source for older material - they still are - but they are now getting much more current content, including the Harvard Law Review and all the Georgetown law journals. Apparently 84% of their journal titles are now available with current full-text content. And they index the remaining 16%, so you know about it even if they don't yet have it.
Their recent blog post makes it all clear.
They also index external content, which they describe thus:

The External section type contains links to law review articles that do not reside inside the HeinOnline database. These are electronically published law review articles, usually not distributed in print format and only made available online via the web. As these articles do not fit the typical structure of a bound book with pagination, they do not work within the HeinOnline database model. Therefore, we have included links to these articles in the search results in order to provide you with even greater access to resources that supplement the content available in HeinOnline. Providing links to external law review articles allows you to conduct your research in one place and on one website.

 Get to HeinOnline via the quicklinks on the Law Subject Guide. Definitely worth taking the time to discover what's there, and definitely worth looking at the guides in their Help pages.