I'm in the process of having to support users in a number of countries (marked red on the map) which are quite far away from where I'm located (marked in yellow)
Hong Kong time is UTC +0800, which means that when I'm into my third cup of coffee, they are shutting down their workstations. Unless I get up beastly early (which will be happening towards mid February) there is little oportunity for quick communication. I hate the bit where I send a message and only get an answer the next morning.
The FoxClocks plugin for Firefox and Thunderbird help me keep track of their time.