Peace sign:

int i,j,d;main(){for(;i<44;i+=2)for(j=70;j;putchar(!j?10:" #"[(d<520&&d>250)||
(d<520&&(abs(35-j)<3||(i>17&&(abs(j-i-17)<4||abs(70-j-i-17)<4))))]))d=(35-j)*(
35-(--j))+(21-i)*(21-i);}


Another peace sign, output is a PPM image file this time:

int _,P,e,a,c,E;main(){puts("P4\n256 256");for(;_++-65536;)P=(_&255)-128,e=(_
>>8)-128,a=e*e+P*P,c|=(a<16383&&(a>9409||(abs(P)<16||abs(abs(P)-e)<20)))<<7-E
++,E-8||(putchar(c),c=E=0);}


Yin-Yang:

int q,Q,w,z;_(o){w=q-10*o;z=Q-20;return w*w+z*z;}main(){for(;q<40;q+=2*!(Q%=40
),putchar(!Q++?10:_(2)>400?32:".*"[w<0?(_(1)<99|z>0)&&_(1)>7:z>0&&_(3)>99||_(3
)<7]));}


Sieve of Eratosthenes, give the program a numeric argument:

#!/usr/bin/perl  # Mauro Persano/coder # http://ghettographics.org/mpr
$_= X x shift;   #         `A witty saying proves nothing.' - Voltaire
while($_){++$i;print($i+1,"\n")if/^X/;s/.(.*)/\1/;s/(.{$i})./\1x/g}



Last update:  Fri Feb 24 14:21:18 BRT 2006