What can I do with this old porch light?

clean, spray paint it and put battery operated fairy lights inside

Clean it up a bit and hang it somewhere with a plant in it. I think it would be adorable. Or a battery candle. Or get a small led lantern, take off the handle and Rub and Buff (hardware and craft stores) the base to match the brass.

Give it new life as a mini Christmas diorama.

Make an awesome terrarium

Yes, I think they pack a lot of punch as far as character, for their size. A person could do several on different themes and switch them out according to time of year, such as Halloween, etc. Thrift stores and garage sales might be a good place to score inexpensive items to arrange inside.

If you choose battery operated mini lights, make sure you use re-chargeable batteries. They are more expensive at the beginning, but the mini lights, even though they are tiny, eat batteries like crazy, and the rechargeable ones last almost forever.

Make a fairy garden inside it!

Put a solar light in it and hang it on your porch or in your garden

Turn it into a bird feeder. Leave 1 side open and put small plastic dish inside to hold the birdseed

Clean it, paint it and turn it into a cute lantern

Hi, Clean it up and make a Clock!