My favorite Disney souvenir was a gift from someone else's trip! My former co-worker got me an Alice in Wonderland teabag/spoon caddy that I fell in love with. On my own, I found the tea-for-one set that matched on eBay and then DSIL surprised me with another one when she went later that year.
My favorite one that I bought for myself is my stuffed Sully holding Mike. I laugh whenever I look at it because I BEGGED my husband to relax the 'no stuffies larger than your hand' rule so I could get it. Oh yes, 42 years old at the time and I was worse than any child begging for a toy.