·Time Warner Cable
·Verizon Online DSL
Speedtest.net can do multiple streams. You just need to find a server that's capable of pushing those kinds of speeds to you.
I tend to use speed tests from the likes of lg.softlayer.com rather than speedtest.net when trying to test a really fast connection, partially for the reason that those speed test sites have significantly less load and thus will get closer to the full speed of the port on the server side.