Uh...
Enemies which is a duh answer.
I can make 250 gold in about 2 minutes of fighting just undead level 33 brigands.
Oh look I just got 38 gold in under 20 seconds.
Wow.
If you said sailing I think your more caught up in the fun of it.
I can see why.
Should have read it better and I did. lol
I put sialing for best way but posted the fastest.