Patent Lens, a free international patent database maintained by CAMBIA, a non-profit research institute located in Caberra, Australia, now has RSS capability. Once saved in an RSS news reader such as Bloglines, searches conducted in Patent Lens will be periodically checked for new patents and will alert you of new "hits".
Patent Lens contains 4.3 million US patent documents, 268,000 EP patents, 538,000 PCT applications and 10,000 Australian patents.