re: How much of an emergency fund do I really need?

yes to the 6 mo living expenses, but please seriously reconsider your vague idea NOT to contribute to your 401K. go do some reading so you understand the tax advantages of contributing to said account.

if you're dying to start building a portfolio, go ahead. but don't make it a priority over a 6 mos emergency fund, an IRA contribution, and a 401K contrib. you can fund it with your "play" money, then it won't break your heart if/when the market undergoes a big correction.