blah.js

#!/usr/bin/env node

var Web3 = require('web3');
var web3 = new Web3();

web3.setProvider(new web3.providers.HttpProvider('http://localhost:8545'));

var fromAddress = "0x9e9e6b41a1959325371fd9a8c47ad5b5d761dbe7";

// md5 hash of a file
var code = "27c7650985ca463499b9e3e21bee20e7";
var hexCode = web3.toHex(code);

// just trying to put the md5 from above onto the blockchain
web3.eth.sendTransaction({from: fromAddress, data: hexCode, gas: 3141592}, function(err, address) {
  if (!err) {
    console.log(address);
  } else {
    console.log(err);
  }
});
/*
with gas: 3141592 the following error comes back

Error: VM Exception while processing transaction: stack underflow
    at Object.InvalidResponse (/Users/esell/node_modules/web3/lib/web3/errors.js:35:16)
    at /Users/esell/node_modules/web3/lib/web3/requestmanager.js:86:36
    at XMLHttpRequest.request.onreadystatechange (/Users/esell/node_modules/web3/lib/web3/httpprovider.js:118:13)
    at XMLHttpRequestEventTarget.dispatchEvent (/Users/esell/node_modules/xhr2/lib/xhr2.js:64:18)
    at XMLHttpRequest._setReadyState (/Users/esell/node_modules/xhr2/lib/xhr2.js:354:12)
    at XMLHttpRequest._onHttpResponseEnd (/Users/esell/node_modules/xhr2/lib/xhr2.js:509:12)
    at IncomingMessage.<anonymous> (/Users/esell/node_modules/xhr2/lib/xhr2.js:469:24)
    at emitNone (events.js:91:20)
    at IncomingMessage.emit (events.js:185:7)
    at endReadableNT (_stream_readable.js:974:12)


without the gas set this error comes back:

Error: Error: base fee exceeds gas limit
    at runCall (/usr/local/lib/node_modules/ethereumjs-testrpc/node_modules/ethereumjs-vm/lib/runTx.js:111:17)
    at /usr/local/lib/node_modules/ethereumjs-testrpc/node_modules/ethereumjs-vm/node_modules/async/dist/async.js:3686:9
    at replenish (/usr/local/lib/node_modules/ethereumjs-testrpc/node_modules/ethereumjs-vm/node_modules/async/dist/async.js:882:17)
    at iterateeCallback (/usr/local/lib/node_modules/ethereumjs-testrpc/node_modules/ethereumjs-vm/node_modules/async/dist/async.js:867:17)
    at /usr/local/lib/node_modules/ethereumjs-testrpc/node_modules/ethereumjs-vm/node_modules/async/dist/async.js:840:16
    at /usr/local/lib/node_modules/ethereumjs-testrpc/node_modules/ethereumjs-vm/node_modules/async/dist/async.js:3691:13
    at apply (/usr/local/lib/node_modules/ethereumjs-testrpc/node_modules/ethereumjs-vm/node_modules/async/dist/async.js:21:25)
    at /usr/local/lib/node_modules/ethereumjs-testrpc/node_modules/ethereumjs-vm/node_modules/async/dist/async.js:56:12
    at Object.async.eachSeries (/usr/local/lib/node_modules/ethereumjs-testrpc/node_modules/async-eventemitter/node_modules/async/lib/async.js:130:20)
    at VM.AsyncEventEmitter.emit (/usr/local/lib/node_modules/ethereumjs-testrpc/node_modules/async-eventemitter/lib/AsyncEventEmitter.js:42:9)
    at Object.InvalidResponse (/Users/esell/node_modules/web3/lib/web3/errors.js:35:16)
    at /Users/esell/node_modules/web3/lib/web3/requestmanager.js:86:36
    at XMLHttpRequest.request.onreadystatechange (/Users/esell/node_modules/web3/lib/web3/httpprovider.js:118:13)
    at XMLHttpRequestEventTarget.dispatchEvent (/Users/esell/node_modules/xhr2/lib/xhr2.js:64:18)
    at XMLHttpRequest._setReadyState (/Users/esell/node_modules/xhr2/lib/xhr2.js:354:12)
    at XMLHttpRequest._onHttpResponseEnd (/Users/esell/node_modules/xhr2/lib/xhr2.js:509:12)
    at IncomingMessage.<anonymous> (/Users/esell/node_modules/xhr2/lib/xhr2.js:469:24)
    at emitNone (events.js:91:20)
    at IncomingMessage.emit (events.js:185:7)
    at endReadableNT (_stream_readable.js:974:12)
*/