Sometimes I need my upload channel be as free as possible, but I also don't want that it affected the download speed of amule. So it would be nice if I could bind upload limit to current download speed, so when amule is waiting in queue, the channel would be free for other services, and in (relatively rare) moments when amule is downloading in full speed, it would also upload at the same speed (so it would be fair participation in p2p network).