A Fistful of Euros have interviewed a ‘world expert on botnets’ about the impact of last month’s cyber attacks on Estonia:

The botnet traffic was distributed globally, with some of the botnets being bought. However, many of the attacks were not by a botnet, but rather by a mass of home users using commands such as ping to manually attack Estonian sites. As they coined in Estonia, this was a riot, and not just in the streets. Many different Russian-speaking forums and blogs (the Russian blogosphere?) encouraged people to attack Estonia using crude commands or simple tools. Others used more advanced techniques.

Interestingly, although the attack wasn’t all that large compared to other previous global attacks, the impact on Estonia was proportionally greater, because of its increasing reliance on its network infrastructure.