They are like...the only points I have ever managed to actually use. The airline miles pile up because of random restrictions that make them unusable (and I refuse to use miles for like...$250 flights). Can't upgrade because I don't have full fare tickets...can't buy the flights I want because there are no more award fares...etc.
Recently spent my Marriott/Ritz points on a leatherman skeletool cx, because you need an absurd number to actually get anything...
But starwood? Between their generous transfer agreements to other programs, and the relative availablilty of either award nights or cash and points stays...they seem pretty easy to use (although their network is smaller than some...especially since they don't have wide-reaching low-rent chains). My Starwood credit card has gotten my some nice stays. Stayed at the W in montreal for a few nights last year, have a single night at the W in Fort Lauderdale next month (stopover on the way back from Key West really).