Actually, I’ve always replied with “Alive”. In the past year it got a lot more attention, comments and laugh than usual, with people feeling the urge to say that it was a great achievement of me.
Anyhow I loved the colors part. I’m peachy is a delight. If I want to get a similar effect in Italian I would have to say something that translates as “I’m a flower” . I guess I’ll go with that sometimes!
Thanks for these entertaining thoughts :)