Need to travel all the time? And getting frustrated to adjust your clock to the correct time? Why don't you get yourself an International clock? Just rotate your clock to the city where you are. See the picture below.
However, this International clock has a limitation in handling daylight saving time. Some countries in the different hemisphere have a reversed schedule and the starting times vary from country to country.
If you want to create one by yourself, this website has a step by step instruction. Have fun :)