I've put some thought into a crossover with Skyrim, tell me what y'all think and if people like it I might try writing it. This description assumes some familiarity with both worlds, feel free to ask questions:
As ordered Menderash sets the Rachel on a collision course with the Blade Ship, but the two ships end up hooked on each other and begin hurtling down to the planet below. On Jake's orders Marco, Tobias, and Jeanne get into an escape pod which lands near the Skyrim/Cyrodiil border. As they try to get their bearings, Marco runs into a band of Stormcloaks and is captured with them by the Imperial Legion.
The story proper actually starts just as the executioner chops off the head of one of the Stormcloaks, Marco is trying to find a chance to get away while also wondering how there are humans here, and to a lesser extent what the deal is with the cat guy they intend on executing next. Cue Dragon attack. At one point Marco manages to acquire it, but this has consequences as one would expect from absorbing the life essence of a powerful mystical beast. After escaping Helgen he regroups with Jeanne and Tobias and they set off northwards following the signal from the other escape pod, but things get complicated.
Meanwhile Matthew Santorelli wakes up in Whiterun under the care of the priesthood at the temple of Kynereth. The last thing he remembers is being knocked out during the crash and no one seems to know what happened to Jake and Menderash. He's told that he was saved from a Sabercat by one of the companions, who he then seeks out.
I've got a lot of little ideas about this, to avoid potential spoilers in the event that I actually write this I'll post some of the questions and minor details I thought of:
DNA is the basis for any lifeform, so what happens when you acquire a god?
What if a Yeerk managed to take one of the Greybeards as a host?
Most 'questlines' are already either completed or partially 'completed' with other characters taking the place of the Dragonborn for variety.
The Dragonborn would likely be a Khajiit or an Orc.
What is the One's goal/plan/purpose?
How does the Ellimist, an artificial god, compare to a Deadric Prince, a born god?
How are there humans on another planet thousands (Hundres of thousands?) of lightyears away? Were they put there from Earth, or do we come from Nirn? Or is it something else entirely.
A minor theme in this fic is the collision of magic and science, or rather the lack thereof as magic is 'Simply a form of energy to be harnessed.'
Is there a connection between Earth and Nirn? (Hint: Dragons)
[spoiler=And one more thing]Why are Skirt-na ships showing up all around Skyrim?[/spoiler]