Colors! I really love the bright reds, oranges, yellows and pinks especially! It it also nice that corns are easy keepers, who eat reliably and frozen / thawed prey, don't get too huge or take up much space and are usually quite easy to handle. With thousands of morph combinations possible and their ease of care, it's very easy to collect a lot of them. However, I will say that I don't enjoy handling my corns as much as I enjoy handling my boas and pythons. They are just much more quick and wiggly. Definitely not as "cuddly" as ball pythons! Oh well.....