For benefit of any newcomers to Bangkok, I'll write the warning.

What ajc1970 is laughing about is simply that The Big Mango is in Nana Plaza, a "shopping center" of bars/brothels where the main attraction is hundreds of young and pretty Thai ladies available for rent by the hour.

Besides the free WiFi, and the Thai ladies, there are other attractions to The Big Mango which may also tempt the OP.
First, they have a happy hour, with reduced beer prices.
Second, that bar is reputed to make the best hamburgers in all of Bangkok.

So there you have it:
Free Wi-Fi, plus happy hour, excellent burgers, and lots of attention from young and pretty ladies.
That would be The Big Mango.
Sukhumvit soi 4, Nana Plaza, go up one floor above ground level, then walk to the right.

- Peter
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