Sampling of popular email service providers. These were the most frequent from my list that I was able to eyeball. From an experiment to figure out what percentage of email addresses on an email list use an ISP for email as opposed to a corporate, educational, or military email address.

common-email-providers.txt

gmail.com
yahoo.com
hotmail.com
aol.com
columbus.rr.com
sbcglobal.net
comcast.net
msn.com
insight.rr.com
earthlink.net
wowway.com
att.net
live.com
terra.com.br
verizon.net
mac.com
roadrunner.com
juno.com
me.com
windstream.net
wideopenwest.com
neo.rr.com
bigpond.com
embarqmail.com
uol.com.br
yahoo.com.br
alltel.net
netzero.com
ymail.com
adelphia.net
bellsouth.net
bigpond.net.au
woh.rr.com
ig.com.br
netzero.net
optusnet.com.au
peoplepc.com
austin.rr.com
ameritech.net
cox.net
rocketmail.com
zoominternet.net
hughes.net
yahoo.co.uk
hotmail.co.uk
mindspring.com
charter.net
adfarrow.com
frontier.com
googlemail.com
bright.net
ozemail.com.au
bol.com.br
excite.com
seanet.com
fuse.net
aim.com
iinet.net.au
bigpond.com.au
rrohio.com
prodigy.net
iprimus.com.au
riopreto.com.br
tpg.com.au
cs.com
pacific-re.com
columbusrr.com

how about icloud.com?