Felted acorns, seen first here and here. It turned out that I had on hand almost the same colors as Stephanie's. The peachy color was dyed naturally years ago with I-don't-know-what. The boys' acorns turned out nicer and less lumpy than mine. I think they rolled and felted the wool more gently in the beginning. I was too impatient.
Since you asked, how-to's for making felt balls or beads (then you can just roll them into more of an oval egg-shape, if you wish, towards the end): good instructions for making small ones and for working with kids here, Martha's pretty version here, more here, and here. Gosh, I wish I'd taken a peek at these first.
More acorny and squirrely stuff:
How could I have forgotten this?: the squirrel and acorn clip art from the MSLiving mag last month.
Wooden acorns like the two mixed in above: here (scroll to bottom of page), or if you are like me and would love to someday get them in bulk so as to have an entire bowlful, then here. Crafty idea for using them here.
Stephanie's amazing and sweet squirrels here, here, and here.
Wee Folk Studio, of course.
Sewn & crocheted woolen acorns from here. Sewn, scented acorns, sold here (scroll down).
Crocheted acorn pattern, free here. Intricate knitted Leaf and Acorn lace pattern, free here. Fiber Trends' Acorn Lace sock pattern. Again, Adrian's Squirrel and Oak Mitten pattern free here. Another mitten pattern here (scroll down, on right hand side, just under "Min favoritvante fran Dalsland").
Crate and Barrel: acorn ornament, candlepot, bowl, and squirrel ornament.
Anthropologie: Felt squirrel and acorn ornament.
Vintage wooden acorn jewelry: pins here, here, here, here, necklaces here, here, here, bracelet here.
Beautiful wooden acorn needle and thread holder here (scroll down).
Pictures: acorn, squirrel (via Mecozy), or just go type in "squirrel" or "acorn" in the search box at Flickr. The squirrels pictures are numerous, sometimes bizarre, and often with hilarious captions. Mr. Acorn. :)
Stencils/templates: acorns, another acorn, oak leaves, or better yet, trace around pressed leaves.
Acorn boxes here, here, here, and this tiny one from an article about making gift boxes in MS Living December/January 1992:
Enough? Anything more to add? I'd love to know of anything else out there that you know of.