You don't want to know what time the sun's highest in the sky in various places around the world, though - you want to know what time people are likely to get to work, when people will be heading off for lunch, and when they'll be back. And that isn't as simple as knowing when it's 9am or 12 noon everywhere, because cultural assumptions about working hours and lunch hours are as variable as the alignment of timezones to actual astronomical noon. What you actually need is to keep an eye on people's Skype presence indicators.