I did a search on SDMB and couldn’t find any discussion, and tried a quick search engine with no luck. I heard that Mormons have something called “magic underwear.” Anyone know anything about this?
Check out LDS garments. This may be what you are referring to.
Sorry, that’s LDS garment.
They’re also called “temple garments”
I have never heard them called “Magic underwear” (giggles)
Or you could get information from a site which is not anti-Mormon.
Mormons.org has a much more respectful explanation of the garments, without all the snide comments. There’s another article by a former General Authority here.
Being curious and after considerable searching, I was able to find a picture of the **temple garments.
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It seems that Barbie was also a mormon.
Basically, they look like the one pieces that women used to wear-with drawers and attached camisol. Hmm…would you be allowed to use a pretty embroidered vintage thingie?
Thanks, everyone, for the comments, links, etc. More homework for me! I appreciate it. I tried asking a Mormon who denied any knowledge of such things. It only made me more curious. Have a great weekend and holiday, if applicable!
Good question, Guinastasia. Actually, temple garments are manufactured by the Church, and sold in distribution centers usually located by a temple or stake center. Women’s garments do have nice lacy trim on them, and come in a variety of fabrics. They do look a lot like Victorian underwear. Men have less choice–big surprise there. 
Most people nowadays wear the two-piece garments, I believe. It’s much more convenient–just ask the cast of Star Trek: The Next Generation.
And yes, they do come off when necessary, if you get my meaning. 