i watch most of アニメ 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 としょうかん, ライブラリ of older アニメ too. they're almost all subtitled though. あなた can watch it for free with commercials, または subscribe to it (which i do). あなた can also watch Crunchyroll on devices like a PS3, XBox360, and several smart phones.
link Funimation - the official site for the アニメ 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 あなた watch the first several episodes of many of their dvd series dubbed. if あなた subscribe to them, a large quantity of their dvd としょうかん, ライブラリ becomes available to watch (i don't subscribe).
link Hulu - they have a large としょうかん, ライブラリ of アニメ dubs (subs if a dub isn't availabe). あなた can watch many of their shows for free with commercials in it. if あなた subscribe to Hulu Plus, there's もっと見る episodes that あなた can watch, plus あなた can watch it on devices like a PS3.
link Viz アニメ - the dvd dubbing company's official site. あなた can watch many of their shows on their site (powered によって Hulu).
link YouTube - they have a ton of アニメ series often dubbed that あなた can watch with commercials. i'm not sure if they can be watched on devices like a PS3 または 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 アニメ episodes または 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 あなた might be able to watch it. they have a good assortment of アニメ dub series. あなた can also watch it on a PS3, XBox360, Wii, smartphone etc.
link アニメ Network - あなた 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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