Sharp World Clock
http://freesoft.tw/5786/sharp-world-clock.html

PolyClock
http://refly.net/android/%E7%94%9F%...99%82%E5%8D%80/

ZoneTick
https://www.anuko.com/world_clock/index.htm

World Time Buddy
http://www.playpcesor.com/2011/05/world-time-buddy.html

Qlock Time
http://tubaby.pixnet.net/blog/post/...%90%98%E3%80%91

Windows 內建
https://briian.com/5070/a-lot-of-clocks.html