Simply code to rate limit your stdout.

rate-limit.c

/*
 * Simply code to rate limit your stdout.
 *
 * Compile:
 *  - $ gcc limit.c
 * Fun uses:
 *  - $ find ~/Sites/thisisourstop/ -name "*.js" -exec cat {} \; | ./a.out 1000
 *  - $ ./a.out < /dev/random
 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char**argv){
  int c;
  useconds_t stime=10000; // defaults to 100 Hz

  if (argc>1) { // Argument is interperted as Hz
    stime=1000000/atoi(argv[1]);
  }

  setvbuf(stdout,NULL,_IONBF,0);

  while ((c=fgetc(stdin)) != EOF){
    fputc(c,stdout);
    usleep(stime);
  }

  return 0;
}