Sending an email across the Atlantic Ocean does not burn any jet fuel, but the internet is not without its own, huge carbon footprint.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/net-hurting-environment
[2] http://admin.indiaenvironmentportal.org.in/category/author/duncan-graham-rowe
[3] http://admin.indiaenvironmentportal.org.in/category/journal/new-scientist
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/environment
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/energy-efficiency
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/energy
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/web
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/internet
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/carbon-dioxide