If you saw yesterday's Tech Tip and were looking for more on using TCP/IP with bash's built-in /dev/tcp device file then read on. Here, we'll both read from, and write to a socket.
With regular expressions you can perform some mighty fine-tuned search-and-replace in text files, such as changing all the US-style date references (09/22/09) to UK style, (22.09.2009).
Most of us default to wget, curl, netcat and others when in need of network data from the commandline, not knowing, or perhaps forgetting, that bash often provides the support that we need using redirection from /dev/proto/host/port.