Mine has since departed to pussy heaven, but he was a large all black beauty called Ziggy. He was lovely, although he died when he was 13 = so unlucky for him. :(
The best cat I ever had was a big black softie called sake (like the rice wine). We loved him so much,he emigrated with us. We almost lost him in quarantine,as he pined away for us. We had to make an emergency trip from Scotland where we were staying with the in laws...down to Hertfordshire where he was. I'd never been hugged by a cat...but he hugged us when he greeted us. It was as if he could not get close enough to us. He always was a cuddler,and would drape himself over my shoulders...all 14lbs of him!
We lost him two years later on a busy country road during autumn harvest time...he was not very streetwise. One of the saddest days I've ever known. But I feel incredibly lucky to have had him.
In answer to the original question, I was always told that a black cat crossing your path was lucky. (Suffolk).
In response to the more general comments, I think black cats are gorgeous and I really can't understand why they're regarded as particularly difficult to re-home. Up until very recently I would have said that my favourite cat of all time was a big black moggy called Sharka, who lived with me for many years, (He's now been equalled in my affections, but not bettered, by a calico cat and her four wonderful kittens).
Wolfie, gthey can be then again the can scrap with each other as well... there is a third cat, Tonks, she's the matriarch, she's most definately in charge and she keeps the boys firmly in check... despite being small and delicate... ;0)