When the Disney film hadn't even been released in cinemas yet I saw a film listed in release schedules for a March release, called "John Carter of Mars". It's since disappeared from those schedules and from every retail site in the UK; I suspect Disney may have had something to do with that. You can see the title on the IMDB page, originally titled "Princess of Mars", which wouldn't have given them the same search engine results (or, if we're less generous, wouldn't have tricked people into buying it). Anyone paying attention would see it isn't the Disney version, but on a quick scan, especially of search results, a person may not have noticed and made a purchase.
The Three Musketeers
Now, I know what you're thinking; there are loads of Three Musketeer versions. But there is only one that came out a few months before the recent Matthew MacFadyen iteration. And even better, the cover looks like it's set in the same era but it isn't; the first few sentences of the synopsis put paid to that mistaken notion, "When Alexandra D'Artagnan, junior National Security Agency officer, uncovers a plot to assassinate the President of the United States..." Sounds awful doesn't it? I wonder how many people read the synopsis though before they make a purchase...
This isn't as bad as some of the others, more amusing than deceitful. And there are three of them (at least). I only saw this recently and it made me chuckle. One film is about a penguin and his friends who meet a human for the first time and the other is about a penguin who can tap dance. How many more will they make with Happy Feet 2 coming out?
Asylum films have a reputation for churning out knock-offs of blockbusters. They're biggest "hit" was an original-ish concept, Mega Shark Vs Giant Octopus but that hasn't stopped them continuing with the copy-cat films. My favourite is probably their Sherlock Holmes; the cover is a very similar colour as the Robert Downey Jr. version, and on a quick glance looks similar. Until you notice the octopus. And the Tyrannosaurus Rex. And the dragons.
Puss in Boots
Another animation, and another one where there has been more than one attempt to create a Deja Vu Film. One tries to be a little more obvious by adding "A Furry Tail" at the end of the original title, but it's still pretty clear that they hope to cash-in on the success of the Dreamworks films.
And finally another cartoon and one I saw a lot of complaints about when the non-Disney version was released. Despite the (slightly) different name, a number of people got confused about these two films. But no doubt as far as the people behind the Deja Vu Film are concerned it made more money then it would have done if it hadn't been called "Tangled Up", so where's the bad?
So watch out when you see a film listed on a website or sitting in a shop with a similar name to a film you're waiting for; it might not be what you expected...