I bought a used vitamix mark 20 today. It works great, I love the size, the price I paid was phenomonal, but I have no idea what it can and can't do. Have any of you actually owned a Mark 20 back in the day? Is it only used for blending? Can I grind wheatberries into flour? Nuts into nut butter? What is the concept behind the posts I read that say I can cook soup? I will probably never be able to afford another vitamix (did i mention I bought this one for $20?), so i don't want to kill this one. Thanks for your help. If someone tracks down an owner's manual for this model, that would be great. I really can't find anything on this model on the internet.