Python one liner to get next ascii char

python -c "print unichr($(echo "$(ascii -st $1 | awk '{print $2}') + 1" | bc))"

Search RAR archives with grep

ls *.rar | xargs -t -I {} rar lf {}  | grep -i <something youre looking for>

The -t option to xargs announces the command line that it is processing (in this case which rar file), and the rar lf lists the files in the rar archive.

Quick webserver w/ netcat

{ echo -ne "HTTP/1.0 200 OK\r\nContent-Length: $(wc -c < <(ls))\r\n\r\n"; cat <(ls); } | nc -l 8080

You can replace <(ls) with whatever script or file to display or command to 

execute that you like 

http://192.168.1.<your ip>:8080  

(Thanks to https://kb.ip-connect.de/index.php?id=422 for the tip)

Or.. if you want to execute a command upon visiting the website url: 

{ echo -ne "HTTP/1.0 200 OK\r\nContent-Length: $(wc -c < <(ls))\r\n\r\n"; cat <(ls); } | nc -l 8080 && <command>

Nc definition of a word from dict.org

$ echo "define wn hello" | nc dict.org 2628
220 pan.alephnull.com dictd 1.12.1/rf on Linux 3.14-1-amd64 <auth.mime> <4420661.15757.1410721786@pan.alephnull.com>
150 1 definitions retrieved
151 "hello" wn "WordNet (r) 3.0 (2006)"
hello
    n 1: an expression of greeting; "every morning they exchanged
         polite hellos" [syn: {hello}, {hullo}, {hi}, {howdy}, {how-
         do-you-do}]
.
250 ok [d/m/c = 1/0/16; 0.000r 0.000u 0.000s]

Pass variables by reference in Bash

function dref() { echo $(eval expr \"\$$1\"); };

$ dref  PATH
/usr/local/bin:/usr/bin:...

Bash recursive subtraction function

#!/usr/bin/env bash

#recursive subtract, arg1 - arg2
function f_r_s() {
if [[ $1 -eq $2 ]]; then
 echo 0; 
elif [[ $1 -gt $2 ]]; then
 echo "1 + $(f_r_s $(echo "$1 - 1"|bc) $2)" | bc;
else
  echo "f_r_s(), reverse the args and try again";
fi;
}