This is not traditional at all, but it is our family tradition to eat this fruit jelly at New Year.  I grew up eating this in summer especially but definitely also for New Year.  This is my aunt's recipe and I am not going to share it without her permission ;-)  but this is basically mixture of orange juice, Sprite (or whatever the version close to it), syrup from fruit can.  You should not use fresh pineapple due to enzyme prohibiting coagulation (canned pineapple is fine).  This is my childhood fav. 

Living in the US for over 20 years, I noticed there's significant difference in food texture preference from East Asia and typical US culture.  I feel American jello is so hard and also the color is not appetizing with bright red and blue for me.  But most of Japanese jello has fruit itself and color is based on fruit juice of choice.  I have discussed differences in how food is promoted in TV commercial; in American commercial, crispy is used often for food promotion while soft and smooth is not as popular as crispy.  Interesting differences...