Well it has to be a penny. ever heard of a lucky penny. Well mine comes with story. On my birthday I found a toned(green yellow and red) 1994 lincoln cent. Ironically my birth year is 1994 and I found the coin on my birthdate.
I carry a 1967 penny in my pocket whenever I go anywhere. Yes, penny, not cent. And large. It's from the UK dated 1967 which was the last year they were made for circulation. Proof were struck in 1970, but in 1971 the UK went decimal and came out with the small penny. My coin started off as something like MS-63 RB. After 25+ years of carrying it around it is probably G-4.