In the Australian Stock Exchange's Sydney data room, which is about the size of a big lounge room, there are six "cuckoos". These are the banks of servers installed by high-frequency traders.

They sit against the wall opposite the ASX servers and each is connected directly into the host by a fat fibre optic pipe. Each cable is precisely the same length by agreement with the ASX so that none gets an advantage; if one server is closer to the input, its cable is looped around to lengthen it.