I should have mentioned that I have both a Gmail and Yahoo mail account. The Gmail gets almost no spam, and the filter catches virtually all of it.
My Yahoo account gets a shitload of spam (easily 200 - 300 a day - not the 10000 someone mentioned, but still a lot), and the filter catches most, but not all, of it.
One thing that may have gotten some of you that only give out your email to friends and family is if they gave out your email to one of those Joke or Prayer or Picture or Saying of the day sites, those are notorious for selling email addresses to scumbag errrr... spammers
My dad did that with my work email, and I finally had to get my employer to give me a new one, because I was getting so much crap.