Well i'll just put some.
Redline
Fate zero.(first half great, second half not so much).
Kara No Kyoukai
Diebuster and Gurren Lagaan.
Berzerk golden age
Hellsing ova.
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Redline: Sick quality and a pretty fun watch.
Fate zero: It had a good thing going plotwise and is pretty HQ in action, but the second half DOES die in quality all around and the plot just.....well it just took a very abrupt dive into shit.(first half is great though).
Kara No Kyoukai: Probably one of my favorite movies of all time.(though there are 7 of them.) Plot goes around girl with a whole bunch of issues who gets magical superpowers to "cut" things. Sounds boring right? Yeah i thought so too except the way its told is phenominal, the soundtrack is great, and its watchable 1-7 but the plot is something like 7,1, 2-5, 6.(could be wrong there) but you won't understand it normally unless you watch it 1-7 first. Action is great, talking and normal animation is HD as well. Focus on plot instead of fanservice is nice also.
Diebuster: Its like GL but in space and with a somewhat more "realistic" plot.
GL: If you watched FLCL then you need to watch this. Nuff said.
Berzerk Golden: Its berserk, if you haven't read it, well......yeah.
Hellsing OVA: Finally a series about violence and action without this bullshit teenage emotions.