Guys- what skills do you wish you'd learned earlier in life?

[Steve85]

Play an instrument. For the fun but also to better appreciate music itself.

I also think about programming a lot. In 8th grade I took a computer class with Commodore Pets and had to write a basic game as the final project. Mine was basically a copy of space invaders and wasn't 100% but I freakin loved it. Had a Commodore 64 at home and wrote programs like making a rocket take off. 3 hours of typing and 30 minutes to save the program to a cassette tape caused interest to wane.

Which reminds me... maybe not skills, but patience and a little more self discipline would have saved me a lot of trouble.