Thailand operates under a bartering system, which means that goods sold by street vendors in markets or in some shops are flexibly priced and you can get a very good deal if you know how to haggle powerfully and politely. Like many aspects of Thai culture, bartering is an intricate system that is easy to underestimate. The trick is to let the vendor make the first offer then ask 'Can you make a discount?' A good benchmark is to offer half the quoted price. Be firm, but make sure that you smile and possibly make a joke - if you are seen as too pushy or aggressive you will not be taken seriously and many traders will refuse to deal with you. Remember not to start to bargain unless you're serious about buying. Also remember that a difference of a few baht may not really make much difference to you, but it may be a big deal to the vendor.
The best bargains can usually be found at large markets. Chatuchak Market in Bangkok is a great place for bargain hunting, as is the night market in Chiang Mai.
Most towns have at least one large local market, where you can find everything from kitchen utensils, cheap clothes, bags and baubles at incredibly cheap prices.
Night markets are also a great place to shop. Usually opening around 5 pm and often packing up as late as 11 or 12 pm, these are also a great place to find a cheap meal, buy fruit and people watch.
Thailand's Floating Markets are much photographed and provide an interesting appeal for tourists. The most visited floating market is Damnoen Saduak, which is also the largest. Most tour operators in and around Khaosan Road offer tours to Damnoen Saduak. However, these days the market is very crowded and sells mainly souvenirs and other tourist items. For a more authentic experience, head to the Bang Khu Wiang Floating Market, which is open daily from 04:00 and 07:00, or the Taling Chan Floating Market, which is open on weekends until around 2 pm.
If you're looking for cheap technology, Panthip Plaza in Bangkok has it all. With 5 floors filled of every type of technological gadget and gismo you could possibly dream of, it is easy to spend half a day here. Remember to barter as most prices are negotiable and seem to be cheaper on the upper floors.
Siam Square in Bangkok is the place to go if you like large shopping centres. There are a wide range to choose from, including MBK, Paragon and Siam Discovery.
Big C is another shopping center chain and can be found all over Thailand in towns, cities and even quite small villages. As well as having its own store, which usually spans several floors, you can usually find dozens of other stores, including international stores such as Boots and The Body Shop.