Matchbox 20 -> Maroon 5
I hadn't heard of Maroon 5 when they were opening for Matchbox 20. And I have to admit I wasn't very interested - I came for MB20, what do I care about that other band? But I liked Maroon 5...really great! I remember how Adam asked us to buy the record if we like the music. As soon as the album was out I bought it.
Album #2 comes this month. Yay!

Ewan McGregor -> Harry Potter
I was a Ewan McGregor fan for some time, but fangirling real people is not for me. Anyway, there was a rumour that Ewan would play Lupin. I had seen the HP movies, but wasn't interested enough to read the books. I asked my pen pal about this Lupin character. I think it was when I visited her that she lend me her copy of Prisoner of Azkaban. Which was a stupid idea...don't start with any part that's not part one! Don't think you know the books if you've seen the films! Anyway, I loved the book (still my favorite of the series) and then bought the others.

CSI -> Supernatural
Okay, that's a bit of a stretch (but not as much as JAG -> Wir sind Helden would be. Wanna hear the story?). All over LJ there are Supernatural fans, but the one nearest to me - kimonkey7 - had some real influence (though I don't really remember how - maybe that endless squeeing about the show's awesomeness). kimonkey7 is on my friendslist for CSI and our silly project ^^.

Alias -> Heroes
Oh, I loved Weiss so much! My favorite character, and I was constantly ranting about how he needs more screentime ("More Weiss!"). But then there was hope: Greg Grunberg got a role in a new show called Heroes. That must be the earliest time in the existence of a show that I wanted to see. And yay: a lot of Matt!

Lord of the Rings -> Lost
I had a couple of reasons to start watching Lost, so maybe this one's a stretch too. One of those reasons was Dominic Monaghan. He hadn't been my favorite Hobbit, but he had been a hobbit.