Euro 2012 Scorers
Check http://javiercejudo.kodingen.com/labs/eurocup/ for the live demo.
Simply playing with web services, comparing response times, and storing the data retrieved to improve performance using a MySQL database and a local JSON file.
I would highlight the use of ON DUPLICATE KEY UPDATE, which I had never heard of before but seems to be pretty useful in cases like this.
It is also interesting that the data is displayed using the same code, independendtly from its source: SOAP/XML, JSON or a database.