My oldest was a 1" feeder comet (paid 14 cents for him) that survived in a predator tank for several months without been eaten. I was so impressed that this fish avoided becoming dinner for so long, that I gave him a tank of his own. I've had him for 12 years now and in that time he has grown close to 11" nose to tail. He's the king of his very own 50gal corner tank. He has developed a puppy-like personality over the years as well. When I come home from work he goes from inactive to totally crazy when he sees me walk in the room. He eats from my hand, and even rubs up against me when I'm trying to clean the tank. Ever give a fish belly rubs?
Having been a fish keeper since I was 5, (nearly 25 years) I can honestly say that, the under-appreciated goldfish, has one of the best personalities in the fish kingdom, closely followed by Oscars. I appreciate this goldfish so much I recently spend $800 on a new setup for him because I was forced to move out of my previous home and had to sell his old setup.
I've kept a lot of "cooler" fish over the years everything from frontosa, to clown knife, to arowana, but they've never held a place in my heart like the goldfish I have now.