The Knol is at http://knol.google.com/k/ira-glickstein/decision-aiding-tool-do-a-trade-study/3ncxde0rz8dtk/5# and it contains a link to a Decision Tool that runs atop the MS Excel spreadsheet that one of my students back at Binghamton University created some years ago and I have upgraded over the years.
"Buying a house, car, pet or PC? Choosing among alternative courses of action at work? Do you and your spouse or your colleagues differ on which choice to make?
"Here is how to get everyone involved to 'put their cards on the table' and make a rational choice that will best serve your needs. A relatively simple Excel-based tool helps you make the right decision, including decisions in the face of uncertainty! It is available for FREE."
If you have a decision to make, have a look!