http://en.wikipedia.org/wiki/Julmust <– Awesome stuff.
It’s not “regional” in the sense that an entire nation drinks the stuff, but it’s unavailable outside Germany/Austria 
Basically coke with fanta, but there’s something about it you can’t recreate at home. I got through gallons of the stuff when I lived Sausage-side.
Does it need to be carbonated? A regional favorite in Buffalo/Western NY is loganberry, which is more like a orange drink type fountain drink except with berries instead of orange. Aunt Rosie’s brand is a local product made by PepsiCo, and there are a few other brands out there, too – although in an opposite way, the Pepsi product is the one most people remember from their youth, the locally made ones are the upstarts.
We have Jones Soda here in the northwest. They became known a few years ago for their turkey, gravy and cranberry flavored sodas. Released just before Thanksgiving too.
Dude! You beat me to it. Fine stuff that I haven’t had in decades.
I’ll mention another that I’ll try later to get a link for: Orange Crush.
And is Grapico still being produced?
In eastern Pennsylvania you can find A-Treat and Kutztown soda.
In the PNW, I’m reasonably impressed by XXX Root Beer and Crater Lake root beer.
It sure ain’t local to me, but I loooooooooove L&P from New Zealand. A friend of mine went there on a vacation, brought some L&P back, and shipped me some. Yummy!
You’re not working hard enough. There are still cases of Moxie in Maine. I would very much like them removed forever.
I believe I once described it as looking and tasting like shoe polish mixed with paint thinner.
I LOVE the Kutztown birch beer, it is my favorite thing about Pennsylvania.
I don’t think you can get it much outside of the Windsor/Detroit area, but Vernor’s Ginger Aleis really good.
I remember Pure Spring soft drinks in the 50s and 60s in Southern Ontario.
I’ve found Vernors in a lot of different areas. I know I can get it in Tennessee at most major places. But still, it is a Michigan drink.
During the Redwings’ playoffs last year, I took a bottle of Vernors to the bar. All these people from Michigan kept coming over to have a drink. We all started having Crown & Vernors…they lost that night in triple over time…I did not feel well the next morning.
L & P goes great with southern comfort or bourbon 
Is one of the things I miss most.
One that needs to be tried that I never saw until I reached Singapore was Kickapoo Joy Juice.
As soon as I saw “joy juice” i had to have some.
Then we also have “anything” and “whatever” … as in, “what do you want to drink?” …“anythings fine”
FYI: San Pellegrino makes a soda called Chino. It’s great stuff–kinda like Moxie on steroids.
In Scotland, it’s Irn Bru.
Apparently it’s not just regional any more, I saw a newspaper article a few months back which said it’s growing real fast in Russia.
I’m back in Spain and I miss my Irn Bru pout
Unfermented grape juice was a regional thing (Navarra, Basque Country, Rioja) until about 15 years ago. Pacharán (blueberry anise) was a regional thing until about 20 years ago. I throw my cane at youngsters from parts south of the Ebro Valley who claim they’ve known pacharán forever 
We get Vernor’s here in the Cleveland area. I love it, especially when I have an upset tummy. The ginger calms me down. Which is not to say it’s not great all the time.
You can get Vernor’s here, Big red as well. Sierra Mist is national, I’ve seen Jones here mostly in specialty places. Once in a great while I’ve even seen Doc Brown.
An I living in a Mecca?
Anyone else have Faygo?
Faygo here in Pittsburgh. Vernors too.
Nehi seems to be a thing of the past, at least in our stores. In high school I had quite a thing for Peach Nehi. I don’t know if it still exists anywhere but I wish I could have one, just for old time’s sake.
Well, these guys do.
Sorta NSFW
I miss A-Treat. They make the only small-brand cola I’ve ever come across that tastes like… cola.
Here in Troll Country we’ve got Solo, a yummy yummy orange soda.
It’s still around. Here’s one Amazon.com vendor who stocks it.
I’ve seen most of the regionals mentioned in this thread here in Indiana at some point or another. There are some “old tyme soda shoppe” type places that carry a wide variety of regionals-- glass bottles of Moxie, Nesbitt’s, Bubble Up, Green River, Nehi, Mr. Newport, Dublin Dr Pepper, etc. A little searching in convenience stores and supercenters turns up Ale-8-One, Bubble Yum, Jolly Rancher, Big Red/Peach/Pineapple, Vernor’s, Crush, Ski, Sun Drop, Double Cola. Most groceries and tiendas sell Mexican and South American versions of familiar sodas, as well as Goya, Inca, the various Maltas, Manzanita Sol, Lift, Sidral Mundet, Jarritos… Asian groceries carry Vimto, Royal, Calpis Soda, the original Red Bull.
Closeout stores are a great place to find sodas. I’ve found some far-out stuff over the years at Big Lots: Cherikee Red, Clamato energy drink, carbonated coffees, Vermont Maple Soda, Nexcite (supposedly a female libido enhancing soda), Dr. Enuf. Health food stores also often carry regional gourmet sodas.
Oddly, we don’t seem to have our own regionals in Indiana… we just happen to be surrounded by regions that do, and on the Venn diagram of distribution maps, we’re at an intersection.
Hard to find around here are the birch beers I had in New England. I really liked Frozen Run Black Bear, as well as the more easily found Polar brand. Polar was interesting in itself, I picked up some odd flavors to cart back home, and everyone liked the dry pomegranate flavor. I also found that I preferred cans and PET bottles of Moxie rather than the glass bottles in Indiana; the glass bottles are made under license and have less of that bitter taste than the New England version. I wish there was a cheap way to get fridge packs of cans shipped here.