Ask HN: Does anyone know of a good academic journal aggregator?

JSTOR, Scopus, EBSCO... are all great resources, but not exactly what I'm looking for.

I'd like to be able to subscribe to academic subjects (i.e. economics, psychology, sociology) and receive daily/weekly notifications when the newest research is published.

I'm yet to stumble on a service that can do this for me - any suggestions?