Spectre:

Tcl actually, but I guess Expect would run it too.

(They're basically the same thing, expect is just the tcl interpreter with a few more functions added)

All one line:

<?php $str = '<?php $str = \'X\'; echo substr_replace($str, addslashes($str), 14, 1); ?>'; echo substr_replace($str, addslashes($str), 14, 1); ?>

ZiggyFish:

<?
    echo htmlentities(file_get_contents(__FILE__));
?>

The OP never mentioned it had to be a quine (it looks like they have names for this (WTF)). 

A BASIC quine without using LIST:

1 READ D$,S$:PRINT S$:PRINT D$;SPC(1);D$;MKI$(8748);S$
2 DATA 2 DATA,"1 READ D$,S$:PRINT S$:PRINT D$;SPC(1);D$;MKI$(8748);S$

An mIRC quine:

//var %q $(| echo //var % $+ q $!( $+ %q $+ ,0) %q,0) | echo //var % $+ q $!( $+ %q $+ ,0) %q

heres my first attempt at a real quine.

sql proc:

create proc q as declare @d varchar(500) set @d = 'create proc q as declare @d varchar(500) set @d = xyx select replace(replace(@d,char(120),char(39)),char(121),@d)' select replace(replace(@d,char(120),char(39)),char(121),@d) 

fun with data uris:

data:text/html,<script>alert(location)</script> 

mfah:

 

AbbydonKrafts:

gremlin:

 No, that doesn't print out its source code.
 

Sure it does. The only time it doesn't is if ECHO OFF was used before running it. Sample output of "TESTBAT.BAT" that only contains the statement "REM":


C:\>testbat

C:\>REM

C:\>echo off
testbat
echo on

C:\>

@echo off

type printme.bat

 

@type a.bat

 XQuery:

1

Worf:

A recent (a couple years ago or so) back, the IOCCC had such an entry. It started out formatted as a Japanese character. Compile, run, outputs source code in the form of another Japanese character. Compile/run, you get a third, and so on for at least 6 times, at which point, you ended up with the beginning character.

yeah, look for dhyang, I forget the year, and it's 4 characters repeating.

Well, for interpreted languages. For compiled languages would be slightly different - a file that generates a compiler error matching the file. Rather non-portable. This works for gcc 4.2.4:

/usr/bin/ld:errorquine: file format not recognized; treating as linker script
/usr/bin/ld:errorquine:2: syntax error
collect2: ld returned 1 exit status

echo "Self"

It's a Self-printing program...

asuffield:

This stopped being difficult when languages gained self-referential capabilities
In Perl:

seek DATA,0,0;print while <DATA>
__END__