Befunge quines seem to be unusually common—a side-effect of the language being both simple and yet unavoidably introspective. Soup! is a Befunge with a twist: it uses its source code as a pattern with which to generate ASCII art. This makes it massively obfuscated to encode the shape of its output. The actual program is smallish, really.
Source
Here's what it looks like:
060p070 p'O80v
pb2*90p4$4> $4$>v>
v4$>4$>4$>4$># ARGH>!
<{[BEFUNGE_97]}> FUNGE!
##:-:## #####* 4$*>4$ >060p> 60g80g -!#v_ 60g1+ 60p60v
#vOOGAH **>4$>^!!eg nufeB^ $4$4$4 $4<v#<<v-*2a:: v7-1g<
#>70g>90g-! #@_^Befunge!! 123456 123456 VvVv!#!>Weird! >0ggv*
^$4$4p07+1g07 ,a<$4< <$4$4< <$4$4< <$4$4< <<#<*-=-=-=-=-* -=-=v*
::48*-#v_>,4$> 4$4$4 $4$4$ 4$4$4$ 4$4$4$ 4$^*!* XXXXXX XXX>
BOINK>$60g1-7 0g+d2* %'A+,1 $1$1$1 $1$1$1 $>^<$ HAR!!! 8888
Befunge_is such_a pretty langua ge,_is n't_i t?_It_ 8888
looks_so much_l ike_li ne_noi se_and it's_ STILL_ ‘88’
Turing- Complet e!_Cam ouflag e_your code!! Confu se_the
hell_out of_every one_re ading_ your_co de._Oh, AND_y ou.:-) ,o88o.
Once_this_thing_i s_code d,_rea ding_it_back_ver ges_on the_imp 888888
ossible._Obfusc ate_the_obfus cated!_Befunge_ debuggers_are__ 888888
your_friends! By:_Alexios Chouchou las... X-X-X-X-X-X-X! 888888
-=*##*=- \*****/ 9797* -=97=- !@-*= ***** ‘"88P’
*!@-*
=*!@-
-=*!@
@-=*!
Output
And here's what it prints when it runs:
GHIJKLM UVWXYZ FGHIJKLMNOP VWXYZA EFGHIJKLMNOPQR WXYZAB EFGHIJKLMNOPQRST XYZABC FGHIJKL PQRSTU EFGHIJ QRSTUV ABCDEF HIJKL OPQRS YZABCD GHIJKLM CDEFGHIJKLM RSTUVW BCDEFG IJKLMNOPQRSTUV ZABCDE HIJKLMNOPQR CDEFGHIJKLMNO STUVWX CDEFGH JKLMNOPQRSTUVW ABCDEF JKLMNOPQRSTUV CDEFGH LMNOPQ TUVWXY DEFGHI KLMNOPQRSTUVWXY BCDEFG LMNOPQRSTUVWXY DEFGH NOPQR UVWXYZ EFGHIJ LMNOPQ UVWXYZ DEFG OPQRSTUVWXYZA DEFGHI OPQRST VWXYZA FGHIJK MNOPQ WXYZAB EFGH STUVWXYZAB EFGHIJ PQRSTU WXYZAB GHIJKL NOPQR XYZABC FGHI WXYZABCD FGHIJK QRSTUV XYZABC HIJKLM OPQRS YZABCD GHIJ MNOPQRS YZABCDE GHIJKL RSTUVW YZABCD IJKLMN PQRST ZABCDE NOPQRSTU YZABCDEF HIJKLM STUVWX ZABCDEF IJKLMNO QRSTU ABCDEF HIJKLM PQRSTUVWXYZABCDEF JKLMNO STUVWX ABCDEFGHIJKLMNOP RSTUVW ABCDEFG IJKLMN RSTUVWXYZABCDEF LMNOPQRSTUVWX CDEFGHIJKLMNOPQ STUVWXYZABCDEFG JKLMNO TUVWXYZABCDEF NOPQRSTUVWX DEFGHIJK MNOPQR TUVWXYZABCDEFG KLMNOP XYZABCDE QRSTUVW GHIJK NOPQRS UVWXY BCDEF LMNOPQ VWXYZ WXYZA XYZAB YZABC
Theory of Operation
The actual executing code is the first few lines of the source; the rest is padding, even some of the bits that don't quite look like it. The code reads itself and prints it out, converting non-space characters to the appropriate alphabetic ones.
The source is actually meant to be obfuscated. It makes use of quite a few Befunge 97 commands, include some really unusual ones. Many of which may indeed have been obsoleted when the Befunge 98 specification was released.