Google RSS 2.0 feeds
While many new news aggregators come with built in Feedster support, allowing you to monitor up the minute what blogworld has written on your keywords, Google still does not offer RSS feeds. While you will already have investigated the Google API if you have to monitor a larger set of keywords or result sets, this might not be straightforward enough for casual use. For this, there now is Diego's Google RSS Feeds. A simple call like this returns a RSS 2.0 feed containing the top 10 results. The Java sources are available. Jason Bell has something similar, just the sources, not a running service though.
