iperf - A TCP, UDP, and SCTP network bandwidth measurement tool

Proxifier - Proxifier extends the advantages of a proxy server to network applications that don't natively support it.

TamoSoft Throughput Test - TamoSoft Throughput Test is a utility for testing the performance of a wireless or wired network.

redsocks - Redsocks is a daemon running on the local system, that will transparently tunnel any TCP connection...

netperf - Netperf is a benchmark that can be used to measure the performance of many different types of networking. It provides tests for both unidirectional throughput, and end-to-end latency. - HewlettPack...

Proxycap - ProxyCap empowers you to divert your PC’s system associations through intermediary servers.