I don’t know about crossed-eyes, but they can get “stuck” that way if you mess with your vision...
http://www.madsci.org/posts/archives/1997-03/858984531.Ns.r.html
The upside-down glasses that you describe were first investigated by George Stratton in the 1890 s. Since the image that the retina of our eye sees is inverted, he wanted to explore the effect of presenting the retina an upright image. He reported several experiments with a lens system that inverted images both vertically and horizontally. He initially wore the glasses over both eyes but found it too stressful, so he decided to wear a special reversing telescope over one eye and keep the other one covered.
In his first experiment, he wore the reversing telescope for twenty-one hours. However, his world only occasionally looked normal so he ran another experiment where he wore it for eight days in a row. On the fourth day, things seemed to be upright rather than inverted. On the fifth day, he was able to walk around his house fairly normally but he found that if he looked at objects very carefully, they again seemed to be inverted. On the whole, Stratton reported that his environment never really felt normal especially his body parts, although it was difficult to describe exactly how he felt. He also found that after removing the reversing lenses, it took several hours for his vision to return to normal.
Much like what those slip proof glasses from The Jerk did. :o