Having trouble getting on Facebook again in Vietnam?
Try Hotspot Shield: http://www.hotspotshield.com
You'll have to download the program, install, then double-click (load) it each time before you try to get on www.facebook.com. Basically it throws up a "shield" allowing you to get around the block. It works by cloaking your DNS or some such.
It will throw up a few advertisements while you use it (a small price to pay). To get rid of those, simply disconnect when you are done with Facebook. You do this by right-clicking on the little Hotspot Shield icon in the bottom right corner of you desktop (Windows).
Additionally, you may want to consider using the facebook app (plugin) Selective Tweets, if you use Twitter:
With this easy add-on, all you do on Twitter is add the #fb hashtag, which allows you to selectively post your tweets to your Facebook status update without actually logging into Facebook.
Hope this helps... for a while.