My experience with mindfulness meditation differs from the standard narrative. Once I had practiced long enough to be able to meditate for 15 min. with no problems, I found meditation much more useful for inducing a concentrated state or taming bouts of internal turbulence than any longer-term effects.
Second this anecdote, and also the parent. I think depending on how you intend to apply it, you may be more or less observant of the short term effects of meditation, esp. mindfulness.
Anecdotally, sitting shikantaza style (just sitting, subtle attention to posture, returning from daydreaming or distraction when you're aware it's happening) has so far had two effects - short term I've found some immediate benefit in terms of being able to apply attention (which was a goal for me), over the span of 1-2 years I've (subjectively) noticed changes in how I react...
So, transferable skills: skills that, upon improvement, increase your ability in other areas (and also improve other, higher-level skills).
A basic example would be reading/writing. Knowing how to read and write allows one to access a huge amount of other skills and resources which are otherwise unavailable. A less obvious example would be clear speech (enunciation). Ability to speak clearly improves one's prospects in a lot of different areas (e.g. professional advancement, dating, etc.).
I'm looking for additional examples. Which skills did you find to be most transferable? Did you become proficient in X, and then found this helped you in many other areas of your life? Please share.
(I tried to find whether this was discussed before, and failed; if it was, I would appreciate the link.)