i watch most of anime online now. but i'm only going to recommend legal, commercial ways (you have to either watch commercials and/or pay a monthly fee).
Crunchyroll - has the most simulcasts (subs that come out the at about the same time that the episode originally airs in japan). it has a huge biblioteca of older anime too. they're almost all subtitled though. tu can watch it for free with commercials, o subscribe to it (which i do). tu can also watch Crunchyroll on devices like a PS3, XBox360, and several smart phones.
link Funimation - the official site for the anime dvd dubbing company. when they get a new license to a series, they often time release the subtitled version of the series for free with commercials (sometime this is simulcasted). they also often let tu watch the first several episodes of many of their dvd series dubbed. if tu subscribe to them, a large quantity of their dvd biblioteca becomes available to watch (i don't subscribe).
link Hulu - they have a large biblioteca of anime dubs (subs if a dub isn't availabe). tu can watch many of their shows for free with commercials in it. if tu subscribe to Hulu Plus, there's más episodes that tu can watch, plus tu can watch it on devices like a PS3.
link Viz anime - the dvd dubbing company's official site. tu can watch many of their shows on their site (powered por Hulu).
link YouTube - they have a ton of anime series often dubbed that tu can watch with commercials. i'm not sure if they can be watched on devices like a PS3 o smart phone.
link Nico Nico Douga - a Japanese youtube-like company. they have an English version and host several simulcasts. i'm not sure how to get to the current page that has full anime episodes o simulcasts though (it's tought to navigate)
link Netflix - only available with a subscription fee, but lots of families subscribe to Netflix, so there's a good chance tu might be able to watch it. they have a good assortment of anime dub series. tu can also watch it on a PS3, XBox360, Wii, smartphone etc.
link anime Network - tu have to subscribe to watch most episodes, but they have a large assortment of dubs and subs and a couple simulcasts. the first episode of most series is available without a subscription.
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