You can also do a really cool and much less
controlled solariztion using a
lighter and a
cardboard sheet.
Just hold the sheet vertically on one side of your horizontal print after it has been exposed to the image. Light the lighter on the near side of the sheet and pass it over the print, allowing the light acces to the work of-art-to-be. Do this for a very short time! Develop the print normally.
This creates a cool image, though it takes a few trys to find the right pattern, and it doesn't require any special fancy equipment.
Also try solarizing prints made from slides, this will reverse the originally reversed tones created by making a negtive print. It'll make the print positive like the slide was originally, but with the added burn and silver depth of a solarized treatment.