I mainly collected Baseball and Football at first, then started collecting Hockey as I became more interested. Collected Basketball to basically collect Jordan cards, but never really went out of my way to buy a lot of product. Today, I see myself collecting mostly Baseball and Football and Hockey since those are the sports I follow most.
I collect soccer and non-sport cards like fantasy art. Love that stuff. I also have a set of Beatles cards. I'm a major soccer fan. I actually posted a question trying to find some info on a set of soccer cards I'm currently collecting. I collected with my dad when I was young back in the late 80s-early 90s, and I've fairly recently gotten back into it and am loving it.