This isn't funny like your descriptions are funny - but one of the things that amused me and brought a smile to my face always, was the squeaky wheel sound Nina used to make as she strolled around. She was the only one of my three pigs who did it and I just loved it.
If I put something in the middle of the room (my pigs had a whole room:
www.guinealynx.info/my-pigs.html ), Nina always had to check it out. Laying a towel over a box or plastic stool was especially fun as she loved to tunnel under it.