For the anniversary series a few years back, the Kamen Rider of that series had to visit the worlds of many of the previous series. For one episode, he was in the world of that season's Super Sentai (Power Rangers) series. It was actually a pretty neat story.
One more reason for me to learn Japanese. It's a pity that a lot of games like that never make it to other language countries (not counting imports), I'd rather have that game than over half the stuff I see on the shelves.