Can Rats Live With Bunnies? Nice Rats?

I really really REALLY hope you don't own any animals. Or small animals, at least.

And what would start is they would fight like MAD, until one of them ended up slaughter the other. So, to answer your question, NO rats can't live with rabbits, or any other species or sub-species of rodent.
You've get to be joking - really. What a ridiculous idea. Rabbits and rats are completely different animals. Rats are rodents and rabbits are lagomorphs. They have completely different dietary, environmental and mental/emotional desires. Your rat could attack the rabbit, and the rabbit is VERY likely to attack the rat. Perhaps you like watching two completely incompatible animals mutilating each other?
Keep them surrounded by their own enclosures, SEPARATELY. Feed the rabbit the correct food for a rabbit, and feed the rat the right food for a rat. If you don't have time to spend with each independently, and are thinking of putting them together to net it easier for yourself, then you should not be getting a rat.
Having cats that get along with your rabbit is adjectives well and good, but they aren't living within the rabbit's nouns, in a closed, confined space. The most "loving" of animals as you put it, will still act like an animal and according to their instincts, regardless of your glowing fantasy of love and harmony. I hope for the animals' sake you take the direction offered to you by the respondents to your question, and decide against it.
pandas cant live with koalas. and chiwawas cant live with wolves, even nice wolfs.

dont do it.

it should be ok i guess long as the rat not have it in mind. The rat wwouldn't wouldnt kill the rabbit (unless it has rabies which i doubt) but it would probably constantly bite it if it fears the rabbit.
Also whether you do this and they end up getting along good, you are gonna have to work double time near the cleaning and bathin for the simple fact it will be easier for them 2 develop hazardous germs that can harm the both of them.
man id be more worried bout the rabbit killing the rat
The rat is a vicious and survivalistic creature and will eventually take out and possibly eat the herbiviore rabbit.
I DONOT Suggest a rabbit living with a rat honestly obtain the rat its own home the rabbit is a scared animal as it is and will probably be scared to annihilation eventually if the rat doesn't kill it first. Rabbits have strong vertebrae legs, that can kill or injure a rat if kicked. Rabbits also have sharp bite to a rattie tail or foot...could do loss of either/or. and rats are survivalist they will eventually kill one another. And you say u have cats ? thats also not the best opinion get a different cage and or i would even consider a different room for the rat each one of these animals own different personalities rabbits and cats are known to get along for the most part of a set. rats and rabbits in the same cage is in recent times pure animal abuse to each animal please consider getting a different cage!
they would probably bring back along just fine.
Answers:    one will always kill the other, give it time...
Not a perfect idea at all!
Is this a devout operation    ?   My hamster is making werid noices  what do i do ?   Please see details. 4 Newt question?   My rabbit is sick! How do I treat it?