(Ellen Messmer, Network World) Spam continues to grow largely due to the growth in malicious botnets. Many botnets are command-and-control systems used by criminals and are still the main way that spam is spewed into your e-mail box. A recent report states that the worldwide spam volume has now climbed to 230 billion messages per day, up from 200 billion at the start of 2010.

M86 Security has created the "Top Ten Most Wanted" Spam-Spewing Botnets list, many of them are believed to be controlled in Eastern Europe by criminals who manipulate compromised systems, mostly PCs, around the world to generate spam:
1. Rustock (generating 43% of all spam)
2. Mega-D (10.2%)
3. Festi (8%)
4. Pushdo (6.3%)
5. Grum (6.3%)
6. Lethic (4.5%)
7. Bobax (4.3%)
8. Bagle (3.5%)
9. Maazben (2.0%)
10. Donbot (1.3%)

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