Code amusant
Trouvé ça et là sur le net.
Code qui s'affiche

En c
char*f="char*f=%c%s%c;main()
{printf(f,34,f,34,10);}%c";
main(){printf(f,34,f,34,10);}
En Lisp
((lambda (x)
(list x (list (quote quote) x)))
(quote
(lambda (x)
(list x (list (quote quote) x)))))
Quelques bout de Postscript

Flocon de neige
%!PS
%%BoundingBox: 94 80 521 568
/side
{dup 0 gt
{1 sub 1 3 div dup scale
side 60 rotate side -120 rotate side 60 rotate side
3 dup scale 1 add}
{newpath 0 0 moveto 1 1 lineto stroke 1 1 translate}
ifelse} def
/star {side -120 rotate side -120 rotate side pop} def
100 200 translate
300 300 scale
15 rotate
5 star
showpage
Une sorte d'arbustre
300 300 translate 2 2 scale
/tree { 1 sub dup dup 0 gt newpath 0 0 moveto 0 70 lineto stroke {
gsave 0 20 translate 20 rotate -0.7 0.7 scale tree grestore
gsave 0 40 translate -18 rotate -0.8 0.8 scale tree grestore
} {pop pop} ifelse } def
10 tree showpage
Yin Yang
42 42 scale 7 9 translate .07 setlinewidth .5 setgray/c{arc clip fill
setgray}def 1 0 0 42 1 0 c 0 1 1{0 3 3 90 270 arc 0 0 6 0 -3 3 90 270
arcn 270 90 c -2 2 4{-6 moveto 0 12 rlineto}for -5 2 5{-3 exch moveto
9 0 rlineto}for stroke 0 0 3 1 1 0 c 180 rotate initclip}for showpage
/D{def}def /d{.00017 add D}D /C{2 copy dup mul exch dup mul}D /g 150 string
D /y .29 D 150 150 8[.4 0 0 .4 -45 -90]{/x -1.2 D 0 1 149{x y /n 300 D{/n n
5 sub D C exch sub x add 3 1 roll 2 mul mul y add C add 4 gt n 5 eq or{exit
}if}loop pop pop g exch n put /x x d}for /y y d g}image showpage
Du c, du c, du c

Vive les pingouins
main(){char*s="6)6%`,%3`0).'/5).3";for(;*s;putchar(*s++^'@'));}
Mandelbrot ASCII
#include <stdio.h>
float o=0.075,h=1.5,T,r,O,l,I;int _,L=80,s=3200;main(){for(;s%L||
(h-=o,T= -2),s;4 -(r=O*O)<(l=I*I)|++ _==L&&write(1,(--s%L?_<L?--_
%6:6:7)+"World! \n",1)&&(O=I=l=_=r=0,T+=o /2))O=I*2*O+h,I=l+T-r;}
Pi
#include <stdio.h>
int b=10000,p,n=6748,k,z[6734],v,f,d;main(){
for(v=b/5;k=n-=14;v?v=0:printf("%.4d",f+p/b),f=p%b,p=0)
for(d=2*k;--k;z[k]=p%--d,p=v+p/d--)p=b*z[k]+k*p;}
Divers

Perl owns me
perl -e'$e="\e[";for$r(0..62){for(0..11){($z,$y,$x,$s,$c)=
(31&(620,5586,14053,496)[$_/3]>>5*($_%3),(7-($r/5))*($_%3-1),
(11-($r/3))*(int($_/3)-2),sin(3-$r/10),cos(3-$r/10));
print$_?"":$e."2J",$e,10-int($s*$x-$c*$y),";",40-int($c*$x+$s*$y),
H=>chr$z+($z?96:10)}select"","","",(30-$r)?.1:1}'
Fractal en sed
echo \* | sed -e ':b;h;s/[ *]*/&|&/g;:l;s/\(|[ ]*\)\*/\1 /;tl;s/|//g' \
-e 'x;s/[ *]*/&&/g;H;g;tn;:n;s/[ *]\{64\}/&/;t;bb'
|