In the UK, various American food brands. Corn dogs, Taco Bell, Dairy Queen, Wendy's, Arby's, Denny's. We eventually got Subway, which was... "a moderate" success...
Canada too to a less extent, one fun road trip game to play when crossing the Can-US border is to list all the chain-stores/brands not available in Canada as you pass them.
Taco Bell has just recently made its way over to the UK. This troper came across a Taco Bell in the food court at Lakeside in Thurrock. Taco Bell did try to break into the UK market previously in the early 90s, with a few branches around Greater London, but it proved too unpopular to be profitable. According to That Other Wiki there are five in UK, and one is on an airforce base. Same goes for Wendy's, which was scattered around London in the 1980s.
Kellogg's used to distribute Brown Sugar Cinnamon Pop-Tarts in Canada but stopped many years ago, citing poor sales.
White castle was once available in Malaysia back in the early 90s. Now they're but a distant memory to those who still remember them. Taco Bell, however, is a far more straightforward example of No Export For You- they've never attempted to enter the Malaysian market at all, and the closest restaurant is in Singapore.
You can even get this within the same country. Bojangle's doesn't exist outside a few southeastern states.
According to the Irish who visited the United States, the Irish LOVE Mountain Dew. Unfortunately for them and the rest of Europe, it's not manufactured there.
Conversely, our American Cousins have never been able to experience (if that is the correct word) UK grown fast food companies like Wimpy and Spud-U-Like.
Hong Kong used to have Domino's, which has been replaced by Pizza Box. No comparison.
Importation of firearms, at least in places where they aren't banned outright, often comes under heavy and somewhat contradictory restrictions. In particular, the importation of pistols into the United States is done on a "points" system that rewards points for things like target sights or all-steel composition, and deducts them for things like small size or caliber. In particular, the .380 caliber Glock 25 cannot be imported into the US (the other Glocks are imported with fragile target sights, which are removed and replaced with the stock sights by the importer), and the Walther PPK has a specific US-only model called the PPK/S, which gains enough points for importation by using a larger Walther PP frame.
Google has blocked access to any service other than Web Search and Gmail for Iranians. Given the fact that they might copy a nuclear warhead kernel from Google Codes or use Chrome for their devilish affairs, or worse, use Google Earth to choose a nuclear bomb test field, it's a logical thing to do.
A electronic age update on embargoes? No new 24 episodes for you!
Most people in the US and in the UK think of Slayers as purely an anime franchise with some manga here and there; only so many recall that it actually began as a series of light novels. Fifteen novels surrounding the main story exist, along with over thirty prequel novels (chronicling the adventures of Lina and Naga) and even a Crossover story. Indeed, Tokyo Pop only licensed the first eight novels of the main series (in which the first two seasons of the anime are based off of), and they are very hard to come by.
Also, only one manga adaptation of the series was officially translated.
The three-volume diaries of Higuchi Ichiyo. This is especially maddening since many commentaries on her work note that the diaries were better than most of her fiction!
Pretty much any European comic, aside from Astérix and Tintin.
Papercutz has been starting to publish Smurfs comic books that haven't seen an English translation for years.
Some wholesalers and distributers from the US ban international shipping, mostly due to the African shipping scams that have surfaced recently.
Phenomena, a great norwegian fantasy-book-series is only released in Norway, Sweden, Denmark, Finland and Germany, according to many, much better than Harry Potter. Might be a case of afraid that it might become Bad Export for You.
Richard Wagner's Parsifal was not allowed to be produced outside Bayreuth or the United States (the latter only saw performances of it due to a court ruling from 1903 that allowed the New York Metropolitan Opera to perform it unabridged, though Wagner's family subsequently blacklisted those involved from performing in Bayreuth) as long as it remained in copyright.
IDW's Doctor Who comic book can't be sold in the UK because of licencing reasons (since othercompanies already have the licence for UK Doctor Who comics.
Oreos are unavailable in Hungary (except in specialty import stores), due to the success of the local Oreo clone called Pilóta. It doesn't help that nowadays both Oreo and Pilóta are made by Kraft.
