Published on 2011-02-16 by John Collins. Please follow me on Twitter for more:
Ars Technica have recently published a series of fascinating (at least for those of us interested in web security) articles on the ongoing difficulties between HBGary, a security consultancy firm, and Anonymous, a collective of computer hackers.
The articles are well written and are worth reading in sequence:
The last one in particular is well worth your attention: it provides a detailed breakdown of some common attacks like SQL injection, brute force password cracks, and social engineering.