Being the tightarse that I am, I use a cheap Casio watch

. I just subtract 10 or 11 hours, depending on what time of year it is.
Besides, It's getting harder to read those tiny bezels masquerading as flight computers on them expensive types of watches

. Ahh, the wonders of ageing
I use my Palm Pilot to work out them complicated calculations such as PNR's, conversions, etc. Plus it's in colour!