Little Java class, to generate leet speak content. This may be used for passwords generation.

LeetSeek.java

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashMap;
import java.util.Map.Entry;
import java.util.Random;
import java.util.Scanner;

public class LeetSeek {

	/**
	 * @param args
	 * Terminate with CTRL-D
	 */
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		LeetSeek l = new LeetSeek();
		while (scan.hasNextLine()){
			

				String s = scan.nextLine();
				System.out.println(l.getLeet(s));
			
		}
		scan.close();

	}

	public HashMap<String, String[]> substitutions = new HashMap<String, String[]>() {
		/**
		 * 
		 */
		private static final long serialVersionUID = 1L;

		{
			put("A",
					new String[] { "4", "@", "/\\", "/-\\", "?", "^", "α", "λ" });
			put("B",
					new String[] { "8", "|3", "ß", "l³", "|>", "13", "I3", "J3" });
			put("C", new String[] { "(", "[", "<", "©", "¢" });
			put("D", new String[] { "|)", "|]", "Ð", "đ", "1)" });
			put("E", new String[] { "3", "€", "&", "£", "ε" });
			put("F", new String[] { "|=", "PH", "|*|-|", "|\"", "ƒ", "l²" });
			put("G", new String[] { "6", "&, 9" });
			put("H",
					new String[] { "4", "|-|", "#", "}{", "]-[", "/-/", ")-(" });
			put("I", new String[] { "!", "1", "|", "][", "ỉ" });
			put("J", new String[] { "_|", "¿" });
			put("K", new String[] { "|<", "|{", "|(", "X" });
			put("L", new String[] { "1", "|_", "£", "|", "][_" });
			put("M", new String[] { "/\\/\\", "/v\\", "|V|", "]V[", "|\\/|",
					"AA", "[]V[]", "|11", "/|\\", "^^", "(V)", "|Y|", "!\\/!" });
			put("N", new String[] { "|\\|", "/\\/", "/V", "|V", "/\\/", "|1",
					"2", "?", "(\\)", "11", "r", "!\\!" });
			put("O", new String[] { "0", "9", "()", "[]", "*", "°", "<>", "ø",
					"{[]}" });
			put("P", new String[] { "9", "|°", "p", "|>", "|*", "[]D", "][D",
					"|²", "|?", "|D" });
			put("Q", new String[] { "0_", "0," });
			put("R", new String[] { "2", "|2", "1²", "®", "?", "я", "12", ".-" });
			put("S", new String[] { "5", "$", "§", "?", "ŝ", "ş" });
			put("T", new String[] { "7", "+", "†", "']['", "|" });
			put("U", new String[] { "|_|", "µ", "[_]", "v" });
			put("V", new String[] { "\\/", "|/", "\\|", "\\'" });
			put("W", new String[] { "\\/\\/", "VV", "\\A/", "\\'", "uu",
					"\\^/", "\\|/", "uJ" });
			put("X", new String[] { "><", ")(", "}{", "%", "?", "×", "][" });
			put("Y", new String[] { "`/", "°/", "¥" });
			put("Z", new String[] { "z", "2", "\"/_" });
			put("Ä", new String[] { "43", "°A°", "°4°" });
			put("Ö", new String[] { "03", "°O°" });
			put("Ü", new String[] { "|_|3", "°U°" });
		}
	};

	String getLeet(String replace) {
		Random r = new Random();
		String input = replace.toUpperCase();
		HashMap<String, String> current_substitutions = new HashMap<String, String>();

		for (Entry<String, String[]> e : substitutions.entrySet()) {
			current_substitutions
					.put(e.getKey(),
							e.getValue()[r.nextInt(e.getValue().length)]);
		}

		StringBuilder sb = new StringBuilder();
		
		
		for (int i = 0; i < input.length(); i++) {
			String subs = current_substitutions.get(input.substring(i, i + 1));
			if (subs != null && r.nextBoolean()) {
				sb.append(subs);
			} else sb.append(r.nextBoolean()?input.substring(i,i+1):replace.substring(i,i+1));
			

		}

		return sb.toString();
	}

}