First my "arty" picture of marbles - the toy of memories - ask any old person and they will give you tails about playing with marbles as a child (well my grandparents certainly did!).
And then about the "fine motor flicking"...
"Flicking" is a fun fine motor activity that can really help a child develop their fine motor skills. Flick by opposing each finger and thumb in turn (you can use either hand and when you get good use both together). Flicking can increase motor planning and accuracy, fine manual dexterity and can strengthen the muscles in the hand.
As you can see we were "flicking" the marbles... we had all sorts of games, for example; flick them the furthest, flick them onto the target, flick them to hit another marble and flicking two at the same time seeing if they could crash.
If you don't have any marbles (or you are worried about your children putting marbles in their mouths) you can scrunch up paper and flick that or make small balls of playdough or use peas.
Have fun flicking! And do have a look at the other photos in the "memories" photo gallery.