Frequent-flyer e-mails

YAPTA (www.yapta.com) is a flight-search engine that finds options for you based on your flight dates, times and preferences. It tracks airfares on flights you want and notifies you via e-mail if the prices change.

Now YAPTA also notifies you when award seats become available for which you may use your frequent-flyer miles. Frequent-flyer programs currently supported include those of the airlines Alaska, Continental, Delta, United and US Airways. The service is free to use; the site carries advertising.