Originally Posted by bhatnasx
Note that most taxis, ...there is a toll (not sure what it is off the top of my head) that you will have to pay - so make sure you pull some baht notes out at the ATM at the airport - smaller bills are better.
One good tip I picked up from somebody else is the tollbooths are a great way to make change from large bills! Say you get 1000B notes from the ATM - you'd be in a quandary to pay the taxi driver at the end because they won't have change. So when you get to the tollbooth, hand over the 1000B note (don't let the taxi driver pay for it) to the taxi driver, he gives it to the toll booth operator and returns the (now) small change to you.