No one has been officially assigned. St. Isidore of Seville (d. 636) has been suggested, probably because he compiled one of the first encyclopedias, a summary of knowledge in his day.
St. Jude, patron of impossible cases, could be helpful on certain days. So could St. Anthony of Padua, finder of lost objects. I nominate St. Peter of Alcántara (d. 1562), a Franciscan with a reputation for extraordinary patience!