Taxis (not airport)., Rangoon
Tourists are usual targets for taxi drivers as like elsewhere they tend to overcharge them.
In some cases cars not signposted as taxis will stop in order to offer you their services. You can get in but first (as with regular taxis) negotiate the price first.
Where you'll most certainly be hassled by many taxi drivers is at bus stations, as soon as you get off the bus (in fact just by the last doorstep of the bus)