From The Economist, June 26 1999, on Ehud Shapiro’s research:

  “In theory, it would then be possible to place a computer inside a cell, along with a suitable collection of rule molecules, and program it to generate particular RNA sequences in response to different circumstances. This RNA could be used by the cell’s internal machinery (as natural RNA is) to synthesise a useful protein. In other words, it could produce drugs on demand, inside the cell. Computing in a test tube may be clever, but computing inside a cell would be the stuff of genius.”