diff --git a/lib/bitcoind.js b/lib/bitcoind.js
index 85914ea0..92e9657d 100644
--- a/lib/bitcoind.js
+++ b/lib/bitcoind.js
@@ -5,6 +5,7 @@
  */
 
 var net = require('net');
+var crypto = require('crypto');
 var EventEmitter = require('events').EventEmitter;
 var bitcoindjs = require('../build/Release/bitcoindjs.node');
 var util = require('util');
@@ -334,6 +335,29 @@ Block.isBlock = function(block) {
   return block._isBlock === Block._blockFlag;
 };
 
+Block.prototype.hash =
+Block.prototype.getHash = function(enc) {
+  if (!this._hash) {
+    this._hash = utils.dsha256(this.rawHeader(), 'hex');
+  }
+  return enc === 'hex'
+    ? this._hash
+    : utils.dsha256(this.rawHeader());
+};
+
+Block.prototype.rawHeader = function() {
+  var res = new Array(80);
+
+  utils.writeU32(res, this.version, 0);
+  utils.copy(utils.toArray(this.previousblockhash, 'hex'), res, 4);
+  utils.copy(utils.toArray(this.merkleroot, 'hex'), res, 36);
+  utils.writeU32(res, this.time, 68);
+  utils.writeU32(res, this.bits, 72);
+  utils.writeU32(res, this.nonce, 76);
+
+  return new Buffer(res);
+};
+
 Block.prototype.verify = function() {
   return this.verified = this.verified || bitcoindjs.verifyBlock(this);
 };
@@ -512,8 +536,14 @@ Transaction.prototype.isNull = function() {
   ;
 };
 
-Transaction.prototype.getHash = function() {
-  ;
+Transaction.prototype.hash =
+Transaction.prototype.getHash = function(enc) {
+  if (!this._hash) {
+    this._hash = utils.dsha256(this.toBinary(), 'hex');
+  }
+  return enc === 'hex'
+    ? this._hash
+    : utils.dsha256(this.toBinary());
 };
 
 Transaction.prototype.getValueOut = function() {
@@ -859,6 +889,33 @@ utils.varint = function(arr, value, off) {
   }
 };
 
+utils.ripesha = function(data, enc) {
+  return utils.ripemd160(utils.sha256(data, enc));
+};
+
+utils.checksum = function(data, enc) {
+  var b = new Buffer(utils.toArray(utils.dsha256(data, enc)).slice(0, 4));
+  return enc ? b.toString(enc) : b;
+};
+
+utils.dsha256 = function(data, enc) {
+  return utils.sha256(utils.sha256(data, enc));
+};
+
+utils._hash = function(algo, data, enc) {
+  var hash = crypto.createHash(algo);
+  hash.update(data);
+  return hash.digest(enc);
+};
+
+utils.sha256 = function(data, enc) {
+  return utils._hash('sha256', data, enc);
+};
+
+utils.ripemd160 = function(data, enc) {
+  return utils._hash('ripemd160', data, enc);
+};
+
 utils.copy = function copy(src, dst, off, force) {
   var len = src.length;
   if (!force)
@@ -869,6 +926,8 @@ utils.copy = function copy(src, dst, off, force) {
 };
 
 function toArray(msg, enc) {
+  if (Buffer.isBuffer(msg))
+    return Array.prototype.slice.call(msg);
   if (Array.isArray(msg))
     return msg.slice();
   if (!msg)