If you have an OPeNDAP-enabled version of mexnc, then instead of pointing rslice at a file, one can point it at an OPeNDAP url. It should basically work the same way as if you were looking at a file that was local to your filesystem, though.

Example 4.4. Using CBLAST OPeNDAP URL for Startup Argument

>> url = 'http://ahab.marine.rutgers.edu:8080/dodsC/cblast_2002-017/avg_day_61-95';
>> rslice ( 'url', url );