Phuket is an island of Thailand. It's nice tropical place. Hitchhiking would be awesome were it not for the notorious taxi mafia, that band together with the corrupted police. In touristy areas almost any car will double as a taxi. When hitchhiking in Phuket you have to have to specify at least 3 times that you are not going to pay. "No money", "no taxi", "free ride", rinse and repeat.
The taxi mafia also causes heavily inflated prices so if you probably don't want to take a cab, ever. If you want to avoid the hassle it's probably best to rent a motorcycle for 200 baht a day.
guaka (talk) had a nasty experience with a guy who suddenly wanted 500 baht for a short ride. He then actually called the police. The corrupt police was actually ready to go to the police station so guaka (talk) settled with paying 400 baht (100 baht was not enough). (This was after 4 very nice rides across the island, including a free veggy dinner in a restaurant.)
See also http://phukettuktuks.com/