Definitely GMT, I don't want to be working off the midnight of some other country. Though that is obviously selfish.

 LMAO ~ more activity overnight than for days ~  LOL

Moving from GMT (or UCT if you insist) would cause too much confusion globally. Even Swatch time had to have a common reference point, although they conveniently moved it to their HQ.

I like Milko's proposal. Speed should be measured in furlongs per fortnight.