My one friend uses a cob striker. I watched him with it once. Nice sound. You probably can make your own corn cob striker. If you can find a way to buy a typical striker (Primos Purple-heart wood striker comes to mind), then take the handle off of it (somehow) you'll have a good start. Then when ya eat corn off the cob in the summer, cut off what would seem like a good handle, bore a hole into the one end, glue it in, and let it dry. That's what would make sense to do, but I've never done it. I might try it tho, now that you mention it.
What other kind of strikers would you like to make? Corn cob is the only one I know of. Now what's interesting is a turtle box slate call. Yep, ya find the shell of a turtle, wedge a piece of slate in there, and ya got one heck of a call. I think you had to use one specific type of shell (I'll look it up).
Good luck!