"The e-mail addresses we use can influence the impressions we
make on other people"

http://science.slashdot.org/article.pl?sid=08/08/13/1226231&from=rss and 
then select link to download .pdf study

(I was intrigued by this research.  The ISPs of the mail I receive 
registers for me, and I check out domains that aren't ISPs on the web, 
and tend not to pay so much attention to the left side of the address. 
Sylvia)

www.peoplewho.org