Here's a link to a paper pieced baby food jar.
http://www.winnowing.com/babyjars.html
I've made several quilts using the regular sized "canning" jars. There are so many fabulous fabrics with items you might keep in a jar, candies, nuts & bolts, money, dice, bugs of all kinds, fruits, veggies, buttons, etc. I find them lots of fun to make and people love them. Especially kids. They can be a sort of "I Spy" quilt. These might make a fun trade.