Comets:  Comets are common goldfish with a little more oomph.  They have longer, more flowing tails and come in the same colors, some with white added to the mix so you have pretty orange and white fish with flowing tails.  The cream of the crop, when it comes to comets, is the sarasa comet.

Sarasa comets:  These fish are not just yellow or orange, they are RED, deep brilliant red-orange with white patterns (or sometimes white with red patterns).  If I could get just one koi with the same beautiful red coloring and snow white markings that these fish
have, I would be ecstatic!  Sometimes when I stop by to look at the koi, I see one of these I just can’t resist and take it home.  After all, my two smaller ponds need beautiful fish too! 

Shubunkins:  I love these.  They come in an unbelievable variety of colors and patterns.  There are browns, reds, blacks, midnight blues, sky blues, whites--sometimes all on the same fish.  I have heard these referred to as “poor man’s koi”, but I think that would be like calling a koi a “rich man’s goldfish”--I’ve bought plenty of them, and not because I couldn't afford to buy a koi, but because these were just much prettier than any of the koi that were available for purchase.

All of the above varieties are very hardly, probably will live in your pond for four to seven years, and all will reach eight to ten inches, growing through their entire lifetime.  For those interested in something a little fancier that might have to be taken in and kept over winter in an indoor tank, there are also a number of fancy goldfish varieties.  I personally don’t keep any of these varieties outdoors, since my outside fish stay outside all year, but I would probably be tempted if I had, say, a small, protected pond on a deck.  There are fantails, orandas with their cauliflower-like head growths, lion-heads, which lack a dorsal fin, moors (jet-black fantails with protruding eyes), and ryukins, with their high, humpy
backs.  There are also some even more bizarre varieties, such as celestial eyes (doomed to look forever at the heavens) and bubble eyes, which have a strange fluid filled sac (easily damaged) under each eye.  All of the above also come in veil-tailed versions as
well, where you have more tail than fish, and these long, flowing tails definitely add to the beauty of the fish.  A lot of people say that the fancies swim slower and have a hard time competing for food when kept with other varieties, but I donut think that is so much a factor to keeping these fish outdoors--to me, the problem with swimming slower is that they would have difficulty escaping from predators.  If you have the perfect place and a tank indoors to overwinter them, I'm sure you would enjoy some of these varieties in your pond also.