Fiji Water. $30 for a case of water that runs about $3 for Safeway generic brand. Delta miles never posted (though others had no issues). Never again.

Would have to agree that rental car miles are so low that they rarely trump discounts. Idine is just gravy from the one participating restaurant that I normally frequent.

Currently the US Airways grand slam seems like it would require an awful lot of time and effort assuming you start from scratch and would not otherwise have reason to book a single transaction. Though the payoff is probably good for retirees and others who don't value time.