Some Links We Like

1. Can a company called Dwolla drastically reduce vendors’ credit-card fees? (HT: Anthony Farrell)
2. A potential “game-changer in the field of [organ] transplantation” — stem cells from the donor may replace anti-rejection drugs.
3. Teaching math in prison. (HT: Arts & Letters)
4. Writer’s block? New study on the best time of day to be creative.