If you know your timezone you can easily update your forum profile to always show your local time for everything (people's posts, etc.) for reference, also other great tools are government and international websites, try
www.time.gov for starters - Many of the websites also have their own web calculators that are very easy to use. Bottom line, if you can find where you are on a map of the globe, and you have a watch or clock handy, you can punch in the info in one of those websites and find the local time anywhere else on the globe, and yes, it will "magically calculate" it for you.
...And if you're running Windows, you can just double-click on the clock on the taskbar in the corner of the screen, and you'll have a tab there for time zones that will help you out right there.
Sorry, I'm not trying to insult your intelligence, but this issue is very, very easy to get around thanks to modern technology.
Edit: Attached is an example of what I get when I double-click the clock on the taskbar (Windows). Your results may of course vary.
Note the text next to "GMT" and the number.