After space jump, what's the next big stunt?

(CNN) -- Felix Baumgartner jumped from the edge of space. James Cameron plunged to the ocean's lowest depths.

Baumgartner broke the sound barrier. Cameron discovered an "alien world."

Call them daredevils, explorers, neither or both. No matter what, their record-breaking solo feats, backed up by teams of specialists, literally raised and lowered the bar for human achievement.

So, for others aspiring to chart new terrain, what's next?

We asked for your ideas.