Our friends at Modern Self just turned us on to these ceiling tiles by Talissa Décor that install easily over that ugly popcorn texture common in so many apartments. According to this article the whole process can be done pretty easily with a utility knife, putty knife and some adhesive. The tiles are light weight molded polystyrene that can be easily removed when you move if your landlord requires you to get rid home improvements upon vacating. White tiles (which you can of course paint to your liking) are $3.99 so you can get away with this project fairly inexpensively.