This site has quite a few original documents that have been scanned and are available primarily in the document center area. Other areas of the site include text transcripts.
The Document Center houses many New England And Miscellaneous Early American Documents. You'll find document scans of wills, deeds, land transfers, warrants and others. They consist primarily of documents found at auction and according to the web site "are included here in the hopes that the genealogical content will be of value to users." So, what you'll find is quite at random and often quite rare. But it's worth a visit.
Here's the link to the main site.