Well I do not know how it is in other states, but here in the europe it is a issue, when ever one takes a hot bath, the mirror in the bathroom get fogged up and take some time to clear for one to use it again, the best way to make it fog proof is to take regullar shaving cream a plam full [depending on the size] and spread over the mirror then clean it with the toilet paper. This leaves a thin film on the mirror and it does not get fogged for the period of 10 to fifteen days.
Hope this helps some one. 
I know that, everytime I go to swim I always wash the glasses by the shaving cream or shampoo... that's a good idea~~
(I've used these many times myself.)
Just a few things you might not have thought of...
I had never heard of the toothpaste method for removing permanent magic marker from assorted materials, (especially plastic) until I went looking for an easy solution.
Gel toothpaste seems to work the best, but any type will do in a pinch. Just spread some on wherever the magic marker is and scrub!
Use paper towels, an old toothbrush, etc.
You can also use toothpaste to help remove permanent marker on clothing/fabric - just be aware of what kind of material you're attempting to clean.
Silk, satin, leather, lace... things like that need a little extra care.
Try using WD-40 for removing the glue left behind by labels.
Need to remove a stubborn label from something made out of polyethylene/polystyrene plastic, (like a CD/DVD case) and don't have WD-40?
Try rubbing it generously with baby oil & letting it sit for about 24 hours.
A lot of labels will peel right off like saran wrap after the baby oil makes the label gum adhere to the paper instead of the plastic.
A few drops of your favorite cologne or perfume in the rinse cycle will keep your clothes smelling great if you run out of dryer sheets or fabric softener. (Just make sure nobody's allergic to it.)
The best glue I've ever used - Gorilla Glue! That stuff will bind anything together.
Gorilla Tape is also incredible.
ATTENTION SECOND-HAND SHOPPERS! - If you purchase any type of cloth-covered furniture from a yard sale, flea market, Goodwill, etc, be sure that you wash any part of the item that can be washed and spray/powder it all over with a good flea killer before you bring it into your house!
If you have a way to store the furniture outside for at least 24 hours while the flea treatment does it's job, this is highly recommended.
I cannot stress this enough, especially for pet owners.
A $5 flea-infested sofa or chair can turn into a very costly entire home pest control problem.
Hope these little tips help some of you out! 
I use this when skiing.. it should work for your mirror too
http://www.catcrap.com/
I just clean the fogged mirror with some towel when I'm finished, but will try that shaving trick u told, thx 
wow.. lol.. thats actually kind of interesting... i live in the US and it bugs the hell out of me... especially because i have to take a shower at 6AM.... lol.... i should try that tonight..
Hmm, shaving cream...
I'm gonna have to try this...
Thank you very much.
But does it really work?
I have not do it before.
Maybe this time i may try you told us. i hope it will work.
Hmmm...
Good idea, I will try it...
Thanx 
Cool thanks. I'll keep that in mind next time I go swimming or skiing
wow, thats a good idea.
ill have to try it out!
thanks! 
thnx for such a good idea. I will surely try it out. 
always learning something new, Macgyver would be proud
I just clean the mirror with a towel if I want to use it, but that's definately interesting, I wonder about the effects of different shaving creams, maybe some crazy scientist with nothing to do will try it with different brands and post the results in some study
great idea will try it . i hope it works