Short: Is there a way to share bandwidth from 2 or more internet connections onto one computer?
Longer: I was thinking of a client on one machine that connects to lets say 3 other computers running a server and all 3 are connected to the client through lan or Wlan but have a second connection to their own isp. A RL example of this could be i have a friend that lives near me and i set up his wireless router so i know his wep key or he just gave it to me. When he is sleeping or is not home i could be using his unused bandwidth or the other way around. He would not even have to be my nextdoor neighbor since we don't need the full 58mbs. To actually speed up downloads of websites or larger files, the client would have to ask the server to download one part of a file and the client uses its own connection to download another. This is the part where I'm not sure if this can work or not, is it possible to download only parts of a file? I'm sure this would work for torrents and for webpages(by splitting up the image downloads to different connections).
A simpler version of my idea is just setting up a proxy on the "server" computer , downloading some stuff on that connection and then switching to your normal connection for some gaming.
Does what i am describing here already exist?
is it even possible ?