Yes, they do make them. Here is a link to one
http://www.us-appliance.com/140nobaflsi.html?trk=smx&ovchn=INK&ovcpn=SSP&ovcrn=SSP&ovtac=PIB
Theresa 
If you mean the battery operated one, yes, they exist, I have one, used it twice and now it's collecting dust. NOT WORTH IT! It takes longer than using a strainer (which is all I use now). Also it gets clogged easily and couldn't handle 2 cups of flour. Here is a link to one:
http://kitchenkrafts.com/product.asp_Q_pn_E_BE0140
Maybe there's another/better one out there that your mom is talking about?
Don't waste your money. Electric sifters are crap.
The tool that gets the job done fastest with the least amount of stress to the hands and wrists is a flat bottomed sieve/sifter mounted to a ring made of either stainless steel or bamboo. Just place it over a large bowl, pour your dry stuff on it, then stir and press it through with a rubber scraper. Takes practically no time. I have one dedicated to sugar that I just pop into a plastic bag when I'm finished, rather than wash it every time.
I too have read NOTHING but bad things about that electric sifter and have opted not to buy one. Even my MIL who almost bought me one as a gift, said the people at the store said it was junk!
I have heard nothing but good things about that flat bottomed sieve. I want one! I usually just use a mesh colander and run a spoon around in it, but of course the sides are mesh too so that gets really messy sometimes...
The tool that gets the job done fastest with the least amount of stress to the hands and wrists is a flat bottomed sieve/sifter mounted to a ring made of either stainless steel or bamboo. Just place it over a large bowl, pour your dry stuff on it, then stir and press it through with a rubber scraper. Takes practically no time. I have one dedicated to sugar that I just pop into a plastic bag when I'm finished, rather than wash it every time.
I'm sorry, but I cannot picture what a flat bottomed sieve/sifter is. 
Do you have a link so I can see something like this? I need something really badly that will make my life easier when it comes to sifting - if you know what I mean. 
TIA
LadyMike
Here are a bunch in different sizes... http://www.instawares.com/sieves.214.3.6945.0.0.8.htm
There's one for just $10 at the top of the page!
I'll have to get one of those because my sifter is falling apart and they don't make them like that anymore, if you catch my drift... 
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