I love The Beatles! I saw Paul McCartney live years ago it was amazing. He sang alot of Beatles songs and some of his own and Wings hits. Have you seen The Beatles movies? They are hilarious!
Oh and I saw a clip of Ringo performing I Wanna be Your Man live with The Beatles on youtube, just brilliant, he was so into it.
I dont have much merchandise, some posters and stickers thats about it. A yellow submarine mug sounds like something I need to have though