You want something that for example prozilla offers.
@anda_skoa:
There is one gain for such thing while downloading from a single server -- when the server limits bandwidths for single connections. Then, if you connect multiple times, you can download faster, because each connection gets its own bandwidth limit.
@all:
But this hasn't got anything to do with slow internet connections. You can never download faster than your ISP allows you
Wheather you have a single connection at 1Mbps or 4 connections at 256kbps, it still equals 1Mbps. The only gain is if there is a limitation of bandwidth for a single connection (and not for an IP, which would sound more reasonable, but is more difficult to control).