Illinois/Wisconsin border is often referred to as the Cheddar Curtain.

http://www.urbandictionary.com/define.php?term=cheddar+Curtain

Forgive me if this constitutes another threadjacking, but this post reminded me of when some folks working on the Dictionary of American Regional English (based out of Madison) came through here last year.  They gave a presentation on how they research regional dialects and slang around the country, and it was totally fascinating.  I don't think the dictionary's available online, but they have some examples of words they're researching on their website...

http://dare.wisc.edu/

I wonder what words made it in there from this neck of the woods.

Hey, Tim, I found your cat!

takes one to know one, Barrett...and I do likes me some cake.

Yes this is what I was looking for.  I guess I also think it is ridiculous to consider Duluth part of the range, mainly because the range refers to a specific set of geological features (Cuyuna, Mesabi and Vermillion Ranges and we are not part of any of them).  The regional dictionary post was definitely not a threadjack, Mary.  Although I obviously invited them with the title for this, thank you for catching that Adam and your cat playing theremin.  

Now ... 

http://www.urbandictionary.com/define.php?term=cake%20eater 
Urban Dictionary has cake-eater sourced around EDINA as I suspected, since I think that's where it actually came from.  The entry notes that it is also used in the film, the Mighty Ducks.  

So, it might be time for some ambitious updater to fix that.  And when you do I suggest this distinction from Barrett's otherwise correct definition regarding Eastern Duluth:  

I mostly grew up in Lester Park, and I would say that the cake eater term largely refers to the Congdon park, Endion and lower Woodland Neighborhoods, but does extend up the shore on the lake side quite a ways and maybe vears left along clover valley or Lester river territory. So this would be a territory that (roughly) runs along the lake from east to west, but cuts off on the UPPER side of London Road until perhaps about 43rd ave E. but certainly 40th where Northland Country Club and Ordean school are and then runs over to about 21st avenue East, maybe 18th, and in some cases as far as the future/old (but not present, thank goodness) racial and economic "red line" of 12th ave E.   This so-called cake-eater territory would be bordered on the upper side by the Cemetery in Woodland or maybe Hartley field.   Even as a student at East we would occasionally call the kids from those more prosperous neighborhoods "cakes." I wish I could draw a map, it's hard to explain with just words.  It's a lot of eastern Duluth, but not all of it.  I would say it definitely doesn't include most of Lester Park, and only a small part of Lakeside, Woodland is a little more suspect since there is a mix of housing stock there, but I'd say probably not upper Woodland, anyway.  

Then again, maybe I'm wrong and Barrett's right, it is all of Eastern Duluth.

Oops, I meant "I'd never heard".  I notice many locals using the present verb in contractions, so it sorta sticks with me.

i've lived in d-town long enough to have become familiar with the term...which was why i was trying to toss a little humor in there.

fail.

my bad.

Did someone say "meat curtains"? I think I just ate a grape.

I recently married a 'cake eater' EHS grad while I am a Denfeld grad, West Duluth born and raised.... I now have a lovely view of the front of EHS.  People from East seem to have no concept of the difference between West End and West Duluth, Norton Park, Riverside and on and on and on.  Its all one big LUMP to them.  They know where the Zoo is though so thats good... What was my point here??  Who knows.