What I found even more interesting:

"The standard varbinary(max) limitation of 2-GB file sizes does not apply to BLOBs that are stored in the file system."

The file size is then, as I understood, only restricted by NTFS. Which could mean: We are already able to store documents bigger than 2 GB into SQL Server. THAT was the most interesting thing for me!

That might explain why NVARCHAR(max) or VARCHAR(max) does not apply: It is not implemented for those data types. Wouldn't be necessary anyway, I know.

Nice question, Steve: Thanks!