What is the smartest financial decision you have made

[Elephant]

Walked out of the guy's office who my residency program recommended as a "financial advisor" when he tried to sell me a HUGE whole life policy.

[Sajimone]

Create a small business aside from the w2 income.. Divert routine tax deductible spending to the business side and create an additional solo 401k!

[J.D.]

Did a Roth Conversion of my entire SEP IRA in 2010 when the taxes could be spread out over 2 years.  Now I have a pretty good sized Roth and no money in IRA's so I'm able to do backdoor Roth conversions for myself and my wife every year with a zero basis

[tigerdoc]

The best financial decision I made was to move my money to Vanguard.  Also refinancing my home from 30 year mortgage at 4% to 15 year @ 2.75% was a good move financially

[Kennyt7]

Other than getting divorced, learning to invest on my own after I read random walk down wall street