Dipterological mailing lists
Chironomid Listserver: http://insects.ummz.lsa.umich.edu/~ethanbr/chiro/internet_res.html
Dolichopodidae and Empididae mailing list: http://hbs.bishopmuseum.org/dipterists/worlddipt.html (you will find the specific details when you scroll down)
Muscidae-L (no webpage available but send an email to Majordomo@cardiff.ac.uk with the message 'Subscribe Muscidae-L'.
Simuliidae: http://www.jiscmail.ac.uk/lists/simuliidae.html
Syrphidae - Hoverfly discussion list: http://lists.nottingham.ac.uk/mailman/listinfo/syrphidae
WGFruitfly-L: http://listas.ciagri.usp.br/mailman/listinfo/wgfruitfly-l
Dipterological newsgroups
bionet.drosophila: search through your newsserver for bionet.drosophila. You can view messages on Google Groups at: http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&group=bionet.drosophila.
Dipterological chatrooms
Asilid Chat Room: http://www.key-net.net/users/swb/laphriini/chat.htm