I bought a recycling bin from Lowe's and turned it upside down to make a hidey house out of it. It works really well, fits several piggies at once, and is easy to clean.
Haha, yeah my neutered boy is in the middle between two of my girls! It looks like they are kissing him on the cheek, but they were actually kicking him out of the house because they got so annoyed with all his pestering!