The Teenage Mutant Ninja Turtles on "The Oprah Winfrey Show". A slight bit of context can be found on Tumblr.
Turtles Forever (full length movie YouTube) was a feature length, 3 episode story from Teenage Mutant Ninja Turtles (2003 edition) released in 2009 as an end cap to that particular turtle continuity. Noteworthy for having the somewhat edgier, somewhat darker, definitely more angular circa 2003 turtles meet up with the recklessly wacky 1987 turtles via an interdimensional travel device. Inevitably they all end up traveling to Turtle Prime, the black and white world of the original comics and are scared out of their minds by the alpha turtles of that dimension.
Mihajlo Dimitrovski (The Mico / Тхе Мичо on deviantArt, Facebook, Blogspot) is an artist most famous for his fanart, and he's got some great A Song Of Ice And Fire illustrations (and others!). [more inside]
From the always reliable Monster Brains (previously) comes the crossover you've all been waiting for: Teenage Mutant Ninja Turtles vs. Predator. But wait, there's more (Google translation): Evil Candy Plans, Forbidden Bat-Love, an awesome batmobile, and lots of plain old what the fuck.
Teenage Mutant Ninja Turtles and Throwdown have a message to impart. [One Link YouTube Post, NSFW Language.]
The toughest Chelonia to every grace the media. Come on. Everyone had to love them at some point, with their pizzas and funny weapons. This page has some interesting sketch art. This one includes the complete cast of the cartoon and movies, with links to their career since said roles. This site, my favorite, has the entire "Coming out of our Shells" tape for download. Remember the classic, Cowabunga?