A preconfigured DataSource with the JNDI-Name: jdbc/sample, which points to
DerbyPool, would contribute to the "standardization" of demo apps. Netbeans
created the datasource for GF v2, so most of the demo applications already rely
on the existence of it.
We used the jdbc/sample datasource for prototyping as well. It is especially
convenient for novice GF users and saves few clicks...