Making the Most of "Waiting Time" on your web site

In checking schedules and fares between Boston and Seattle on the Alaska Airlines site, I was impressed by the promotion that appeared while the database was preparing a list of flight options.

Instead of looking at a spinning symbol, I was reading a short and to-the-point popup for their frequent flyer telling me how to get 1,000 bonus miles.

If you have a database driven web site, do you make similar good use of your web site's processing time?