Waiting 9-10 minutes for pasta al dente allows for a pretty focused practice moment. Putting your phone on speaker while waiting for the next available customer care associate offers a little sight reading opportunity. Computer downloads or virus scans can take what seems like ages-- unless you're working out fingering for a Chopin prelude.
If you're an adult student in the year 2013, odds are you've figured these things out. Spending an uninterrupted hour alone at a piano is a rare luxury for many students.
Effective practice is always focused. If most of your ten minute moment is spent figuring out what you intend to accomplish and how, even if the actual work has to wait until you have adequate time, then you've spent your time well.