I love the idea of a Roth 401(k) and if you could afford to lose the tax deduction of a 401(k) deferral and you have enough of a horizon before you retire.

I just learned that venture capital billionaire Peter Thiel has managed to turn a $2,000 initial investment into a $5 billion fortune inside of a Roth IRA. You may not be able to do that, but with tax rates likely to increase over time, it may make sense to make all or a portion of your 401(k) deferrals as an after-tax play. If you can afford to lose that deduction.