Talk to a npc or read a book to start the miniquest. It goes to a ruin or cave. At the end of the cave you'll fight a tough boss (whetever crature). Once you've done so, a small puzzle.
Like moving some pillars to their possitions, if it's in the right position it'll be lit. Lit pillar = 1 dragon soul. 10 pillars to move = 10 dragon souls. Once the pillars are moved then in the center you'll activate something and get 1 perk point for it. YES, 1 perk point for 10 dragon souls.
With the amount of overhaul, dragon and combat enhancement mods out there, dragon encounters happen frequent, and I for one have 30 dragon souls with no use for it. But I could use 3 perk points.
Just something to think about. Would be neat if somebody realised this as a mod.