You read right; it's an idea for a Ranma/Kirby crossover. Oh what my mind comes up with at the oddest of times.
The idea originated as just a small crackish idea that has managed to evolve into something possibly more. There are basically two different scenarios where this could take place.
Scenario #1: Take the tried-and-true 'Ranma falls into a different spring at Jusenkyou' formula. Only this time, add the fact that Ranma now has the ability to inhale virtually anything and has the ability to copy almost anyone's abilities or characteristics for a certain amount of time. As such, the timeline would end up turning very different.
Scenario #2: This one takes place at the end of the Ranma 1/2 manga. It's a 'what if' to a thought about the cask that everyone is fighting over accidentally contains something different than spring of drowned man water. The reason for this is that the Jusenkyou Guide made a slight mistake and thought he grabbed the man water.
So, what happens is that something different happens that causes the cask to fly at Ranma, break, and spill the water all over him. Needless-to-say, certain individuals aren't happy to see their 'cure' wasted like that. It's then, however, that they notice that Ranma -- instead of being male AND human -- is now a small pink... thing.
With the second idea, there are two possibilities...
1.) The Kirby curse completely overwrote the girl curse, and so Ranma now turns into a small pink puffball with the ability to inhale things like a vacuum cleaner.
2.) The Kirby curse mixes with the girl curse, and so Ranma now turns into a FEMALE small pink puffball with the ability to inhale things like a vacuum cleaner.
Whichever change happens, it's understandable that various people will have a wide variety of reactions to this change. Some could be bad, and some others could be worse.
An extension to this is that due to 'Kirby' awakening/being revived, the small space ship/warp star that Kirby crashed to Earth on eventually re-activates and manages to locate Ranma. Ranma ends up slightly curious over the ship/star and checks it out... only to fall in/on it and accidentally activate it. This causes him to go traveling with no idea how to control it at all.
With this, Ranma would find himself traveling through outer space, randomly visiting a few places, and possibly landing on Pop Star/Dream Land. Whether the video game or anime timeline is used is the question.
One of the amusing things would be to see Ranma manage to copy certain abilities from those in Nerima.
Ryoga: Could end up copying his strength... along with the Bakusai Tenketsu
Mousse: Mastery of Hidden Weapons
Akane: Bad cooking = good weapon
Ukyo: Combat spatula and flinging okonomiyaki from seemingly nowhere.
etc.
Even if Ranma loathes the change of form, he'd still probably find himself interested in the copy ability.