Know what happens when you grow 6 or 7 different types of squash in your
garden and then take an acorn squash and save the seeds and plant them the
next year? So far I have:

Scallop/acorn cross - funniest looking squast I've ever seen lol.
Crookneck/acorn cross
zuchinni/acorn cross
Pumpkin?/acorn cross. Not really sure about this one, but the vine is 10
feet long, growing like a pumpking vine, and setting large round pumpkin
like fruit. Have to wait a week or so to see what they are going to do.

They fruit are very identifiable as the base type, and they are also ribbed
like an acorn squash. Quite funny looking. Moral of the story - squash will
cross with other squash LOL.