Well, that was kind of cool... I just implemented xml feeds for search queries in CAREO. Took about half an hour.
You can subscribe to any term you would normally enter in the search field in CAREO. Not sure how/if it would handle multiple words or anything. I guess as long as they're URL encoded it should work.
Anyway, here's how to subscribe:
Just replace "MYSEARCHQUERY" with whatever you want to look for. The top 10 results, sorted by relevancy, are returned. Searching for some stuff will be slow (something like "image" will get a bajillion results, which must be sorted for the top 10...)
The usual caveat applies: THIS IS PRE-ALPHA, PROTOTYPE CODE. IT MIGHT BREAK, OR JUST PLAIN DISAPPEAR. You've been warned.
UPDATE: URL-encoding the query seems to work fine for multiple word queries... i.e., to search for "biology video", set "query=biology+video"