If you remove the LNB (electronics) a small child could use it for a snow saucer.
Some other uses (especially if you like playing with electronics): Place a microphone close to the focal point of the dish and you have a directional microphone (identifying song birds?). At rite aid they used to sell a really low end "hearing aid" that had a microphone in the main unit and ear buds. I tried it and it worked reasonably well.
If you were in a very fringe area for either wifi or even cell coverage and you placed your wifi antenna or cell phone at the focal point, you'd pick up a stronger signal. About 10 years ago, I found that I could pick up a neighbor's wifi from about 1/3 mile. If you need to adjust the coverage of your home router, placing the dish in certain spots (trial and error) could either boost or reduce the signal.
Bird bath.
Yard art
Or put it in the trash....