Found in 3 comments on Hacker News
aespinoza · 2011-09-08 · Original thread
I really enjoyed this one:

Beautiful Architecture: Leading Thinkers Reveal the Hidden Beauty in Software Design - http://www.amazon.com/Beautiful-Architecture-Leading-Thinker...

vibhavs · 2009-08-16 · Original thread
I suggest Beautiful Architecture from O'Reilly.

http://oreilly.com/catalog/9780596517984/

http://www.amazon.com/Beautiful-Architecture-Leading-Thinker...

It's similar to Beautiful Code (also mentioned here) with various chapters on different, independent topics: e.g. Facebook's data-centric architecture, Xen hypervisor, etc.

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