1. A computer-implemented method comprising: receiving a first classification value associated with an e-mail message that is an output of a first classification tool and a second classification value associated with said e-mail message that is an output of a second classification tool, said first classification value and said second classification value indicative of whether said e-mail message is spam; and generating a single, aggregated classification value for said e-mail message by combining said first classification value and said second classification value using a fuzzy logic-based voting mechanism, wherein said first classification value and said second classification value represent probabilities P 1 and P 2 , respectively, and said single, aggregated classification value represents a combined probability P combined , and wherein said fuzzy logic-based voting mechanism includes a voting formula comprising: 
 P combined =( P 1 ×P 2 )/(( P 1 ×P 2 )+(1− P 1 )(1− P 2 )).
1. A computer-implemented method comprising: receiving a first classification value associated with an e-mail message that is an output of a first classification tool and a second classification value associated with said e-mail message that is an output of a second classification tool, said first classification value and said second classification value indicative of whether said e-mail message is spam; and generating a single, aggregated classification value for said e-mail message by combining said first classification value and said second classification value using a fuzzy logic-based voting mechanism, wherein said first classification value and said second classification value represent probabilities P 1 and P 2 , respectively, and said single, aggregated classification value represents a combined probability P combined , and wherein said fuzzy logic-based voting mechanism includes a voting formula comprising: 
 P combined =( P 1 ×P 2 )/(( P 1 ×P 2 )+(1− P 1 )(1− P 2 )). 4. The method of claim 1 , wherein said first classification value and said second classification value are each is an output of a classification tool using at least one of a domain level blacklist, a domain level whitelist, a heuristics engine, a statistical classification engine, a checksum clearinghouse, a honeypot, an authenticated e-mail system, reputation information, message signatures, and sender behavior analysis.