If you think we're not immune, think again.  ANYTHING connected to the net, whether an email server in your basement ( :) ) or a repeater controller connected to the net in a datacenter is a target.  If the big boys are scrambling, think of what we, with our limited resources, are faced with:

And for a realtime view of what's being sensed by the second largest web crawling organization (the former Internet Security Systems, now IBM X-Force):

Awareness is a good thing.
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