The tray tables on airplanes don't get cleaned after every flight, says Sara Keagle
, a flight attendant and travel blogger. Worse, Keagle says she's seen passengers do "everything from diaper changes to clipping their nails on them." The adhesive, eco-friendly plastic mats usually marketed for kids (available at drugstores and on Amazon.com
) are the perfect size and stick right to the tray table.