New implementation

Be concise.

Be useful.

All contributions dictatorially edited by webmasters to match personal tastes.

Please do not paste any copyright violating resource.

Please try to avoid dependencies to third-party libraries and frameworks.

Other implementations
int main(){char*s="int main(){char*s=%c%s%c;printf(s,34,s,34);return 0;}";printf(s,34,s,34);return 0;}
main(p){printf(p="main(p){printf(p=%c%s%1$c,34,p);}",34,p);}
! See original attribution URL
package main

import "fmt"

func main() {
	fmt.Printf("%s%c%s%c\n", s, 0x60, s, 0x60)
}

var s = `package main

import "fmt"

func main() {
	fmt.Printf("%s%c%s%c\n", s, 0x60, s, 0x60)
}

var s = `
main = putStr s >> print s where s = "main = putStr s >> print s where s = "
c=console.log
q=decodeURIComponent('%22')
l=[
"c=console.log",
"q=decodeURIComponent('%22')",
"l=[",
"]",
"for(i=0;i<3;i++)c(l[i])",
"for(i=0;i<7;i++)c(q+l[i]+q+',')",
"for(i=3;i<7;i++)c(l[i])",
]
for(i=0;i<3;i++)c(l[i])
for(i=0;i<7;i++)c(q+l[i]+q+',')
for(i=3;i<7;i++)c(l[i])
public class Quine
{
  public static void main(String[] args)
  {
    char q = 34;      // Quotation mark character
    String[] l = {    // Array of source code
    "public class Quine",
    "{",
    "  public static void main(String[] args)",
    "  {",
    "    char q = 34;      // Quotation mark character",
    "    String[] l = {    // Array of source code",
    "    ",
    "    };",
    "    for(int i = 0; i < 6; i++)           // Print opening code",
    "        System.out.println(l[i]);
x = [["x = [" .. "[" .. x .. "]" .. "]\nprint(" .. x)]]
print("x = [" .. "[" .. x .. "]" .. "]\nprint(" .. x)
<?php $s='<?php $s=%c%s%c;printf($s,39,$s,39);';printf($s,39,$s,39);
program Quine(Output);const A='program Quine(Output);const A=';B='begin writeln(A,char(39),A,char(39),char(59),char(66),char(61),char(39),B,char(39),char(59),B)end.';begin writeln(A,char(39),A,char(39),char(59),char(66),char(61),char(39),B,char(39),char(59),B)end.
$_=q(print"\$_=q($_);eval;");eval;
s = 's = %r\nprint(s%%s)'
print(s%s)
eval s="print 'eval s=';p s"
fn main() {
    let x = "fn main() {\n    let x = ";
    let y = "print!(\"{}{:?};\n    let y = {:?};\n    {}\", x, x, y, y)\n}\n";
    print!("{}{:?};
    let y = {:?};
    {}", x, x, y, y)
}
object Quine extends App {
  val s = 
    """object Quine extends App {
      |  val s = 
      |    ""%2$s%1$s%2$s""
      |  print(s.stripMargin.format(s, "\""))
      |}"""
  print(s.stripMargin.format(s, "\""))
}