The following pitches are for older arms only.
The "forget about it" headlline could be taken 2 ways. If you're the batter: forget about hitting them. But if your a young pitcher... forget learning them! They require larger hands and/or more mature arm joints. We present them here for informational - not instructiuonal - value.
Knuckleball
Kids love to try this but seldom have confidence to throw a knuckler in game situations. (Just as well, the 40-year olds need something to call their own.) Finger tips on seams, knuckles bent (hence name). On release fingertips flick forward killing rotational stability, so seams catch lots of air and ball dances.
Forkball
Takes long, strong fingers. With fingers forked outside narrow seams, the thumb has the best grip and should pull up on release - ending up between the forked fingers. The ball spits out and the resulting spin will depend on the uneven down/side pressure against the fingers. Good luck with this one
There are also a couple of other pitches with weird names and weirder motion. But they are not serious contenders for youth league or high school - bascially because they won't get you to the next level. So we have not yet decided if we will illustrate them - unlikely we will every animate them...
Eephus & FOSH
Picture a big looping curveball that floats high and lands almost on the plate - much like a slo-pitch lob - and you have an idea of what an Eephus pitch is. Not only is this unlikely to get anyone a college career (let alone pro signing), we suspect that even though the motion is effortless (like a knuckleball) there might be hidden starins on the elbow from the over-the-top arm action. As for the FOSH - it stands for "full of sh**" so the less said the better. Besides, there are enough serious pitches to learn.