It is possible to set up a cross-site question filter on stackexchange.com (http://stackexchange.com/filters http://stackexchange.com/filters). As far as I can

It is possible to set up a cross-site question filter on stackexchange.com (http://stackexchange.com/filters http://stackexchange.com/filters). As far as I can tell, it only allows filtering by tags, not full text, so your mileage may vary.