65w plant bulb <-- you might need to play with the wattage depending on you enclosure size / climate. Some people use ceramic heat bulbs but real plants will thank you for a plant bulb.
I go with halogen wide floods, 35-65 watt. Plants love them. If you need "heat" then a normal 65 watt plant/house bulb would do a better job at heating an area.
It depends on your house hold temperatures, the age, species and sex of your chameleon. I like the plant bulbs mentioned above but you may want to have an assortment of wattages to hit your target basking temperature. Your needs may vary throughout the seasons.
I go with halogen wide floods, 35-65 watt. Plants love them. If you need "heat" then a normal 65 watt plant/house bulb would do a better job at heating an area.