Set your glue guns to stun and glue the heck out of flowers onto your lampshade. Fake or felt flowers will probably work best but if you only need it for a day, you could try real flowers. Extravagant! See examples from Mr. Kate, How to Nest for Less, and Creative Home Arts Club.
History buff? World traveler? Day dreamer? This lampshade would be perfect for any of those people. Find a map and attach to your lampshade with some Mod Podge. See examples from Silver Boxes and Pretty Handy Girl.
Let the little kid in you draw on your furniture with some fabric markers or permanent markers. Doodle your heart out and admire your handiwork with light shining through it at the end. See examples from Jade and Fern, Your Home is Lovely, and this lampshade by Rachael Taylor.
Do you have a cool lampshade? Show us the results of your lampshade makeover at firstname.lastname@example.org!