I had a blankie that my Great Aunt knit for me when I was born. I couldn't sleep without it and it showed. It had a huge hole in the middle and an ancient piece of gum stuck in it that never came out no matter how many times it was washed.
When I was 18 I went to a party and stayed the night at a friend of a friends house. The next night when I went to bed I realized I'd left blankie behind and panicked. I made some calls only to find out the girls mother had thrown my blankie in the trash, which had already been picked up. Utter devastation. I'm 36 and would probably still be sleeping with my blankie if that had never happened.
One of my favorite movie scenes ever was when Michael Keaton tries to get his little boy to give up his Woobie in "Mr. Mom"
"I understand that you little guys start out with your woobies and you think they're great... and they are, they are terrific. But pretty soon, a woobie isn't enough. You're out on the street trying to score an electric blanket, or maybe a quilt. And the next thing you know, you're strung out on bedspreads Ken. That's serious."