Inexpensive gift that's for multiple age groups?

This year our finances are tighter than usual and I'm looking to potentially get a single gift (or kind of gift) that works for all the neices and nephews. They are 13 - 24. One younger girl, 2 girls in their early 20s, and one 13 year old and 17 year old boy.

Is there something small that they'd all like or is it better to find something small for each individual? It would have to be something under $20.