I generally use my miles for upgrades. Sure, I'd like to cash in 120K and try First Suite on a LAX-SYD run, but I love Business Class on the 777 and can use those miles to upgrade an inexpensive Coach fare to Business for LAX-SYD *and* SEA-NRT.

In general, I fly overnight when going East, since I lose the day anyway. Since I cannot sleep on a plane, I do not bother upgrading to F/C. However, I usually will upgrade the return leg (early evening) so I can relax (plus the headwinds usually add an hour to the flight time).

As for cars and hotels, well I usually send those miles into airline programs. I use Hertz exclusively, but having to spend $18,000 to get a free weekend in a Prestige Collection car (what I normally rent) seems ludicrous.

As for hotels, I do not use the miles for free rooms. I know Hyatt allows miles to be used to upgrade rooms to suites. Yes, you need to pay the higher rate, but the times I stay at a Hyatt, the rate is high anyway (special events) so that is really nice. As for Hilton and Mariott (my other two), I like Hilton's "Double Dip". I did the Mariott "Take Two/Silver" this year and will see what that is like, as well.