Car Seat Desk

Car desks come in several models, each providing different features. Some have non-slip surfaces, some are secured thanks to the use of a seat belt, some can fold up and double as a briefcase, some have removable trays. Whatever model you may choose, be sure to only use a car seat desk when you are parked, for obvious safety reasons.
Car Seat Desk:

Car Seat Desk pictured: AutoExec – AEFILE-02 – FileMaster Efficiency Mobile Office Work Station – Black