Today and tomorrow are holidays in Thailand for Asanha Bucha, trust Wikipedia with caution, but here is there description of the holiday. On August 2 and 3 government workers will have a holiday, the post office and banks are closed and most large companies will be on holiday- some private companies will still be working.
And street food is hard to come bye (shit!).
Sorry to those thirsty holidayers- these are dry (or mostly) dry days in Thailand; most bars will not be selling alcohol in Bangkok on either August 2 or 3, 2012. In fact, many bars will be closed for both days.
If you get the bad cravings, head to a western hotel or find a local convenience store. You might well be able to buy alcohol in some grocery stores, but many Thai run businesses do not want to sell any alcohol on important Buddhist days.